AKA You have done about all you can do.The only other thing I can suggest is to go talk to someone at the nearest VA facility, they just might be able to help,also as a Colonel he IS still subject to call up by the military if needed.
Just from what has been posted it sounds like he has Post Traumatic Stress Syndrone PTSD. It is a very real problem with someone who has gone thru a very stressful situation, with some people it does not show up right away. Someone thst has it doesn't even know it most of the time,untill something sets it off.
Mine came to light 5 years after I came back,Just being around the smell of diesel fuel brought it all back. I had nightmares, cold sweats, and flashbacks I went to the VA and they hooked me right up.
Good luck with him and thanks for caring.