Letting my child go away with his team overnight

I'm having a lot of feelings about this. My son is in a coed volleyball team at his high school and in February they're going away overnight for a "game" that's more of a Fundraiser. He is a teenager. 15. But I've been through a lot with my baby boy that you all have supported me through. When he was 13 I walked in on my father molesting him and I found out my dad sexually abused my brother for years which he why he left home at 20 and went live in a secluded life in the woods. My father caused my son a lot of trauma. I told my son no and he asked why and I said because he's been wetting the bed so much more lately and I don't want him to be embarrassed. His dad had suggested to me we just pack some depends on pull ups for him to wear and I said no because if he's back to doing this nightly something must be wrong. My son has been upset that I told him no. Me and my brother talked about it and my brother asked me if this was really because he's wetting the bed more again or if I'm scared something is gonna happen to him again where I'm not there to protect him. Honestly maybe it's both? I still feel guilty because my dad is a monster to think I had a monster living in my home. Both my parents are monsters because my mom still supports him. But I'm his mother. I should have protected him. My brother did give me advice as he's also a victim of my father and told me I can't let what happened control my son forever because he let it control him which is why he ended up living alone in the woods for over a decade. My son deserves happiness. He deserves a to have fun. But at the same time he would be away. I don't know every single person who will be there. I don't know if there are some unknown perves. I can't trust my dad. Why the fuck would I trust strangers? It was hard enough letting him go to sleepovers after everything. I'm just scared for him and I think I always will be. My dad is charged and sentenced to 8 years. Why can't I just move on?