broncovet

Maybe Berta will chime in here, BUT it is medical malpractice (1151 claim) when VA fails to diagnose and treat you.  (I beleive it may be called treatment delay.  You were apparently referred for treatment, and "somebody" dropped the ball).  
While my crystal ball is currently on the blink, if I had a choice I would take private treatment over the VA, mainly for 2 reasons:
1.  You get faster treatment in private care than you do VA. 
2.  "Fear" is a big motivator, and private care docs fear a malpractice lawsuit, so they do everything in their power to prevent it.  VA docs dont care..if the Vet does file an 1151 claim, the worst that would happen is they are transferred to another VAMC.  

Keep fighting, Im fighting for the same thing.  If my logic is correct, and you are not working, then you will be "unable to leave your premises FOR WORK" 
Refer to Howell vs Nicholson, as explained by Alex in his awesome post:
https://asknod.org/2014/08/25/cavc-howell-v-nicholson-what-smc-s-really-says/
Its incredible, to me, how VA can award you TDIU on one hand, then say you are not "housebound" by the above defination of "housebound".  
I share your frustration, the VA did that to me, also, and Im in appeals on that very issue.  Howell is a precedent setting case, not some guy making stuff up.  

When you go to a C and P exam, Vets advocates always say to tell the doc about your "worst day", not your best day.  
So, if your pain level was a 9 on thursday, but its only a 2 on the day of the exam, then tell the doc your pain level was a 9 on Thursday.  (Your worst day).  

I will "guess" that "K1" is K, because you can have multiple SMC K's, because you can have loss of use of more than one thing..its not "just" for loss of use of a reproductive organ, there are other things, too.  
For example:
So, if you lost use of one hand, one foot, and your reproductive organ, then you would get SMC
K1 Reproductive organ
K2 hand
K3 foot 

Yes..there is a risk.  The VA has implemented a plan to reduce all Vets who apply for an increase in order to stop Veterans from seeking an increase, thus reducing their workload and backlog, as well as saving money to fund the "next pork barrel" hospital.  Just kidding, tho suprisingly we see this myth propogated by VSO's, VA employees, and even some Vets advocates.  
However, knowledge is power, and you are gonna get that right now!  
The VA has "specific criteria" when they can reduce you, and, if you have been rated over 5 years or are P and T, then they can not reduce you UNLESS you not only Actually improved, but did so while working.  
The VA can not reduce you for applying for an increase, this is NOT a criteria for reduction!  Of course, if you did "actually improve under ordinary condtions of life", then you probably wont be applying for an increase, now would you?  Gee, you get better so to get even with VA you apply for more benefits?  How often is that gonna happen.  
It IS true that VA looks at your whole file when you seek an increase, however, the VA does that anyway, always on the lookout to save money by cutting benefits, especially by Vets who have improved and no longer need benefits, such as they are able to go against all odds, cure incurable diseases and go back to work full time!  
Incredibly, some rather famous Vets did just that, but were still not reduced!   John Mc Cain, Max Cleland are both senators collecting 100 percent and working as a US Senator.  Tammy Duckworth, a 100 percent disbled Vet, not only worked for VA while collecting her 100 percent, but is a big, big shot.  I hear she got out of VA and joined the 2 above, who are 100 percent and are into politics.  
The facts are that VA can/does reduce Vets who improve, but that happens independently of whether or not they apply for an increase.  
While its true, when you seek additional benefits, many eyes will be on your claim, the fact remains that VA has laws, and these prevent reducing Veterans who dont meet the applicable "improvement" criteria as follows:
(Note the 5 year protections only apply to P and T Vets, or those who have been rated 5 years or more):
3.344 Stabilization of disability evaluations. (a)Examination reports indicating improvement. Rating agencies will handle cases affected by change of medical findings or diagnosis, so as to produce the greatest degree of stability of disability evaluations consistent with the laws and Department of Veterans Affairs regulations governing disability compensation and pension. It is essential that the entire record of examinations and the medical-industrial history be reviewed to ascertain whether the recent examination is full and complete, including all special examinations indicated as a result of general examination and the entire case history. This applies to treatment of intercurrent diseases and exacerbations, including hospital reports, bedside examinations, examinations by designated physicians, and examinations in the absence of, or without taking full advantage of, laboratory facilities and the cooperation of specialists in related lines. Examinations less full and complete than those on which payments were authorized or continued will not be used as a basis of reduction. Ratings on account of diseases subject to temporary or episodic improvement, e.g., manic depressive or other psychotic reaction, epilepsy, psychoneurotic reaction, arteriosclerotic heart disease, bronchial asthma, gastric or duodenal ulcer, many skin diseases, etc., will not be reduced on any one examination, except in those instances where all the evidence of record clearly warrants the conclusion that sustained improvement has been demonstrated. Ratings on account of diseases which become comparatively symptom free (findings absent) after prolonged rest, e.g. residuals of phlebitis, arteriosclerotic heart disease, etc., will not be reduced on examinations reflecting the results of bed rest. Moreover, though material improvement in the physical or mental condition is clearly reflected the rating agency will consider whether the evidence makes it reasonably certain that the improvement will be maintained under the ordinary conditions of life. When syphilis of the central nervous system or alcoholic deterioration is diagnosed following a long prior history of psychosis, psychoneurosis, epilepsy, or the like, it is rarely possible to exclude persistence, in masked form, of the preceding innocently acquired manifestations. Rating boards encountering a change of diagnosis will exercise caution in the determination as to whether a change in diagnosis represents no more than a progression of an earlier diagnosis, an error in prior diagnosis or possibly a disease entity independent of the service-connected disability. When the new diagnosis reflects mental deficiency or personality disorder only, the possibility of only temporary remission of a super-imposed psychiatric disease will be borne in mind.
(b)Doubtful cases. If doubt remains, after according due consideration to all the evidence developed by the several items discussed in paragraph (a) of this section, the rating agency will continue the rating in effect, citing the former diagnosis with the new diagnosis in parentheses, and following the appropriate code there will be added the reference “Rating continued pending reexamination ___ months from this date, § 3.344.” The rating agency will determine on the basis of the facts in each individual case whether 18, 24 or 30 months will be allowed to elapse before the reexamination will be made.
(c)Disabilities which are likely to improve. The provisions of paragraphs (a) and (b) of this section apply to ratings which have continued for long periods at the same level (5 years or more). They do not apply to disabilities which have not become stabilized and are likely to improve. Reexaminations disclosing improvement, physical or mental, in these disabilities will warrant reduction in rating.
[ 26 FR 1586, Feb. 24, 1961; 58 FR 53660, Oct. 18, 1993]  

Based on your post, the exam is no longer needed.  
However, THESE ARE YOUR BENEFITS< AND YOUR LIFE, so dont leave it up to chance.  You would look both ways before crossing the street, even if a stranger said its okay to go, so why take a VA employees word for it when its been wrong sooo many times in the past.  
If it were me, I would call the examiner and ask if an exam is needed, that you were unclear.  Then go to the exam if he requests same.  Dont take some GS5's input into the computer gambling it would be correct.  

Of; course I dont know if your sleep apnea will be service connected or not, but if it is, it should increase your rating by 50 percent.  When you use a cpap, and are sc for OSA the rating is 50 percent.  If my guestimate math is correct, combing the 6o percent you are now, plus an additional 50 percent means you should go to 80 percent using the va math.  
Are you currently working?  If you are unable to work, then you should apply for tdiu.  
As far as the other conditions, remember that you wont get paid for any symptom twice.  In other words, if you have the same symptoms with asthma as you do with lung disorder, you get paid for that symptom only once.  
 

It looks like you have 2 out of 3, then.  Current diagnosis, and "in service diagnosis of acute sciatica in 2004 and radical symptoms".  But, I dont like the word "acute".   Here is the definition of Acute:
Acute: Of abrupt onset, in reference to a disease. Acute often also connotes an illness that is of short duration, rapidly progressive, and in need of urgent care.
"Acute" is a measure of the time scale of a disease and is in contrast to "subacute" and "chronic." "Subacute" indicates longer duration or less rapid change. "Chronic" indicates indefinite duration or virtually no change.
end defination
To get VA benefits you need a "chronic" condition.  The VA wont pay you for back pain in the service which is short term and then goes away.  To get paid, you need a condition that continues to bother you now, not an old pain that went away. 
Remember that back pain you had in the service, they already said was short duration and went away.  So, did you have a car accident that caused this?  Did you lift something heavy?  Fall down the stairs or off a roof?  Get beat up by a jealous husband?  Any of these things COULD have caused your current diagnosis, but you have to have a doc say that your military service event
at least as likely as not" caused your condition. 
Do NOT count on the VA to connect the dots between  a "history of radiculapathy since 2004, "  AND  "the Veterans radiculapathy is at least as likely as not caused from an event in military service".  
I do see the connection, I really do. It does not matter what I think, tho.  It does not matter what you think either.  It matters what the doc writes in his report.   But you need a Doctor to state that it means the same thing.  The doc COULD say, "the MRI shows a history of radiculapathy since 2004, "   which means the Veteran's radiculapathy (here would be a good place for the doc to insert other related diagnosis such as IVDS/DEGENERATIVE DISC DISEASE (DDD), LUMBOSACRAL SPINE,) is at least as likely as not due to the Veterans in service injury. 
I believe you have great evidence for the doc to give you a nexus.  But, for whatever reason, the doc did not give you a nexus in the form VA requires.  IT HAS TO BE in the form of "at least as likely as not"  The rater probably has your file in electronic format and he can search for these terms and find the nexus pronto.