He needs to file a claim for depression as secondary to chronic pain due to service connected DDD. He may need to get an independent medical opinion. I would file the claim to protect the earliest effective date and then start to get more evidence. It takes months if not years to get a decision so he has time. Does he go to VA pain clinic? What kinds of pain meds does he get? He needs to tell them how badly his back hurts on a scale of 1-10. The closer to 10 the better. If a person has chronic pain the meds alone will tend to make you depressed. This is common knowledge except at the VA where they are thinking in terms of saving money for taxpayers. Is the VA counselor trying to find an alternative reason for his depression like the fact his mother took away his hobby horse when he was 5 years old? Usually, they will try and convince the vet it is all due to home life or the fact mommy whipped him or dad was a drunk. This is crap, of course, but the VA spent decades convincing combat vets that there PTSD was just due to home life or high school.