Game time needs to be a factor.
You want him socializing and playing 4 player games, not sucked in to an epic quest.
Timeless classic Bally games are the key here.
Anyone of them will do. Pick a theme that resonates with him, buy it now and rebuild everything with him during these last few months before he moves out (this is the important part for both you and future him), and then he will have the confidence and pride to keep it running while he is away and when it breaks down.
Bonus points... if this goes like I think it will in my head... then his senior year you can pull the game home and do a full restoration on the game and make it his graduation present in 4 year.