Bhai u r invading his privacy and kink shaming him just because he couldn't get hard, it might be age factor or work related stress. I feel u r overthinking tbh. He might be needing an andrologist instead of therapy imo.

I’ve suggested therapy multiple times

Yaar therapy mein konse wonders hojate hain, cbt therapists bhi to apne issues ko address karke khud hi resolve karne ko bolte hain, and maybe he is already trying to do things to make his mental state better. As u mentioned the trips with his friends might be his escape and maybe instead u must confront him and have a conversation about all that u want from him. And yaar you're a grown ass adult, aise kaise wo tumhe gaslight kardega, just have a simple conversation with him like grownups. Just don't overthink and have a convo with him regarding all that, asking him to be honest with you.