We are not in the exact same boat – no military experience here. But I can certainly appreciate your concerns.
My son, almost 19, has been crushed by his experiences at school and college. There are some on here who said the military was exactly what they needed and were glad they did it. I guess I would say that if it’s something he’s actually interested in then meeting with recruiters to collect information couldn’t hurt.
I would also consider meeting with his school counselor and a college advisor. We met with a college advisor once – it did cost some money but they are full of information.
I think a meeting with an ADHD coach or a counselor to get more clarity on why he changed his mind about college – is it anxiety and if so what about etc? The more awareness he has about how his brain works the easier it will be for him to match his strengths to the right situation for him – whether that be the military, college, on line college, take a gap year and work or do internships??
Keep us posted on how things go.