Being excessively reclusive needn't be a death sentence. Have you tried to transition to home-schooling[0], which might get the law off your back? If he is interested in gaming, perhaps he could try his hand at game development, or parts of it such as music or art. Spending a couple of hours each day working (with you perhaps) on some skills and then publishing something on itch.io - say a short PICO-8 game - might help open him up a little and give him some street cred with former friends and classmates.
[0] https://www.gov.uk/home-education