AITA for dropping my guy friend after he "accidentally" walked in on my little sister showering?

So l 17F have a friendgroup of 5 people. It's common that we will hang out at eachothers houses, but mine is most popular because it's a bit larger and we have a bigger tv to play videogames on. The group is made up of 2 girls & 3 boys. Last week on Friday we were all hanging out at my house. We were all in my room when Ray, 18M said he was hungry. I told him just go to the fridge to get whatever since my parents weren't home and it was only us and my little siblings. Ray went downstairs to get the food. I thought my little brother and sister were in my parent's room playing mariocart like they usually do, but some minutes after Ray went downstairs the rest of us heard a girl's scream. I jumped up and ran down to see what was wrong, when i came downstairs i saw Ray standing in the doorway of the bathroom before seeing it slam shut from the other side. I yelled "What the fuck?" at Ray and walked up to the door to hear sortof crying from the other side. Ray started to talk but I just told him to get out. He started to argue but everyone at that point was downstairs and yelling at him so he just left. after a few minutes my sister finally let me in the bathroom where i saw she was taking a shower and not just using the bathroom. She then told me when he came in she was in the shower so maybe he didn't see, but we have one of those glass showers so i don't think that's true. Shortly after everyone left. Ray textedune groupenat later that nignt to say it was an honest mistake, the groupchat basically went off for a good hour with texts from most about how weird it was. I didn't believe him. The main reason being that at our school in junior year, Ray mistakenly went into the girls locker room, no one was in there because it was the middle of a class. But when class ended and girls went to the locker room to change out of their gym clothes they saw him halfway closed in a broom closet. He claimed to the school it was a complete accident, and since he didn't really see anyone nude the school gave him3 days of ISS and called it a day. At school today he tried to talk to me while i was walking in between classes and i brushed him off. A couple people were staring as i was ignoring him and he was kinda following me around trying to talk to me. I learned later my girl in the group posted a private story about how he's a perv, and to "hide your little sister" from him. I told the friend to delete it but the damage was already done it had reached at least 60 people at that point and over the weekend it only spread. Now he's texting the groupchat saying we're all "a bunch of snakes" and "lying on him" I do feel bad if it was an honest mistake since he plays football and he's coming up on his senior year so an opportunity could be ruined based off rumors and lies. Sidenote we don't usually use the downstairs bathroom to shower, and when he's been at my house before he's used that bathroom lots of times, which makes me think it was an accident. AITA?