Yeah, sounds very likely.
I mean, just the sentence, “My mother didn’t raise a gay son”… I can see only 2 reasons.
1. He’s gay/bi.
and/or
2. He is so disconnected from what gay is that he thinks parents make kids gay.
#2 doesn’t really fit with the gaydar comments.
I’m glad you got out, regardless of his orientation, and I hope he reads this and it helps him be honest with himself.