Need dad advice

I have three kids. One with my ex and one with my wife. The one I have with my ex is almost 16 and I have a great relationship with him. I've had suspicions he was gay since he was 8. He has always been a little feminine and when he was younger and had toys he would always make the male toys date each other. He hasn't come out as anything though. Why I'm worried is he has a friend and I have a lot of reason to believe this person is more than a friend. But this person is also known for being very very violent. My son has always had issues with getting rid of toxic friendships. He wants so badly to have friends that he has kept friends that were not good to him and I have reasons to believe this is more than a friendship. And this boy is known to be violent. Went to juvi because he harmed his brother. Has an extremely bad temper. I don't know the correct way to go about this. My ex says he hasn't come out as anything and if he's not this could offend him. I'm 99.99999% sure he's gay. But I get her point. Since he hasn't come out as anything I don't know how to navigate this situation. Any advice is appreciated.