Assalamu alaikum - can anyone advise about my brother's strange health issues?

Assalamu alaikum. I'm from Canada and I grew up in an atheist family, and I myself am atheist. There's a family friend I'll call M who is very close to us - more like a brother. He’s one of those people who's insanely good with tech and has a kind of philosophical, poetic way of looking at things. He used to be a firm atheist and did extreme stunts to show paranormal stuff was nonsense, like spending nights in abandoned places said to be haunted. He also had a rough past - using harmful substances and doing shady things. But then he suddenly changed and became quiet and thoughtful, talking about humanity and society and saying he regrets choices that hurt himself and others. After he tried to turn his life around, weird health problems started: severe breathing issues, he can't walk or talk for long, wakes up gasping for air, and has trouble sleeping even when the breathing is better. We’ve seen so many doctors, paid for countless tests, and no one can pinpoint the cause. Some professionals said it might be psychological, so we pursued therapy obsessively. We didn’t tell therapists that he used to do those anti-religion stunts, but surprisingly some therapists - and even some doctors and people who consider themselves atheist or agnostic - suggested it could be related to something like jinn or a paranormal cause. M himself says he doesn’t feel any obvious supernatural symptoms; he’s mostly just frightened to do the crazy stunts he once did to disprove religion. I’m at a loss and don’t know what to do next. If anyone has any thoughts, advice, or similar experiences, please share - we’re feeling clueless and helpless. JazakAllah khair for reading and for any help. ❤❤❤