what do I do now

I posted early this week saying how my bf isn't acting happy at college which my mom and I both noticed. Well now he is "faking sick" to skip fraternity events. He never gets sick and he doesn't have any sick symptoms he just sleeps. His "sicknesss" always comes when he's supposed to be at frat parties during the weekdays. What's hard for him is these events are at his house. I told him to go home this weekend which is an hour away. His parents don't like when he comes home for some odd reason and he doesn't want them to be mad. What do I do I feel bad? I wish he would bring this up but he won't. Thank you!