You should look into Roblox, it’s well known to be widely used by paedophiles, and many of the areas that look suitable for children within the game are not , eg an innocuous looking classroom will have ‘girls love rape’ scrawled on the blackboard, or a play centre will have people performing sexual acts. There’s no way I’ll allow my children onto Roblox. Turkey banned the platform last year due to its sexually explicit content, grooming and cyberbullying aimed at children.
Check out the excellent Nicki Petrossi (Scrolling2Death) on Instagram/YouTube/Podcasts. She really knows her stuff.
As his parent, you can choose to take it all away from him and get your child back. Fully supervise his homework sessions if they have to be screen based, set timers on his devices and password protect all devices in the home. You can also restrict which sites he can access on his laptop. The addiction is real though, so be prepared for withdrawal symptoms. Also, know this isn’t your fault, or his. These games are designed to draw you in and children are not equipped to resist them, nor are a lot of adults.
Yes, boarding school will get him off the devices, but when he’s home (and he will have long holidays) the problem will still be there. I’d really try to deal with his addiction before he goes. We had a similar problem with my DS and Fortnite (watch out for that one, highly addictive), but then we introduced strict boundaries, timers, passwords and time restrictions (such as weekends only) which has worked very very well. Huge tantrums at first, which ended up in a 2 week total ban from his Switch, followed by the introduction of the new rules, but we stuck with it and his behavior has improved enormously. He knows exactly when he can play and for how long. You could try talking to his friends’ parents, they might be feeling the same way?