He might, but it seems like you don't trust him in general. So, you're looking for the most minor changes in his voice to confirm your own suspicions. I do think it's a little odd that he'd say ''coughing on dick,'' but he might be saying that to joke with you? Idk. Personally, I would be put off by a guy who told me he ''hates gays'' and is ''homophobic,'' just my opinion. If he's bisexual, he could be saying that to cover up for his own insecurities, if he isn't gay, then he's a bigot. Either way, that comment would cause me to really think about if I want to be in a LTR with him.
Going out of his way to say how much he does not gay people is a CLEAR sign he has gay feelings. He's does like not gay people because they are living the life he is afraid to. That's why he's angry about the "social norms" etc. So the best he can do is fine a female like the OP who will allow little "gay" things in the bedroom or look at gay porn where maybe a women shows up eventually. In his mind he's still straight because he does these things with a women.