TDIU issues

[Digdug0037]

I put in a intent to file on 19 February 2019, submitted claim for increase for mental health/other specified trauma/stress related disorder in Dec 2019. Was approved and increased from 50% to 70%.  I then submitted for TDIU with my mental health disorder and sleep apnea I have a combined rating of 90% with my 10% tinnitis. I ended up having to submit everything on my own as it was march of 2020 and our VSO shut down the VSO offices and I could not make contact with DAV. I recieved a letter that I may get a call for info from a doctor as they would be doing a records review, I "assumed" since I just had a C&P for mental health in February 2020 that they were using it for review as well. In May of 2020 I recieved a denial letter, stateing I did not qualify for a increase from 50 50% for sleep apnea therefore my TDIU was denied. I stewed on it for a bit and kept rereading the letter when I noticed under the evidence considered, my mental health was never reviewed or even acknoledged. I was kinda stuck as VSOs were still not available at my local VA and I never heard a peep from them at all. I called the Veterans Service Orginazation in the next county over and made contact with a VSO there. Due to Covid, all communication was by phone but I sent copys  and we discussed the situation and decided to ask for a higher level review. I ended up talking to a DRO in February of 2021 on a informal phone call, she noticed before I even said what I thought and said, they didnt even review your mental health. The call was short, she said she was going to look at it and see if there was anything she could find and make a decision without any further delay. 2 days letter on VA.Gov it says the reviewer found a error and was sent back for a duty to assist, and to correct a error. Got scheduled by LHI for C&P which was yesterday, I feel like it went well for me, but after everything so far just seemed concerned something is still not right. I do have a couple questions

1- will the C&P exam go back to the DRO, or will it be sent back to the original VA level who messed up the first time.

2- anyone else have a issue like this? 

More than anything I am just frustrated as I did everything I was supposed to do from the start, and they did not complete the claim as was needed and it ended up costing me more time, I am hoping this is it, not sure how long before I hear back with results of my claim but hoping for the best. 

Please make sure if you get a denial letter, read everything and make sure they did everything proper, because had I not kept reading it I would have never found the error and probaly would of gave up right then. Everyone have a great day.