Why are you guessing the mental issues part? Has the admin given any indications of that in the past?
Because, it sounds to me, that if he was running a free service on his free time because he felt like it, then he doesn’t owe anybody anything. He can simply vanish for the simple reason that he got bored, and that should be enough.
I don’t know, man. To me that’s still speculation. But did say you were guessing, so that’s okay. I just thought that you had a clear indicator of mental issues.
It could very well be that someone started stalking him, or sending him death threats, and he simply said “yeah, fuck this.”
Or that he started the project to get some groupie ass, then got ass, then he was done with it all.
Or he got bored and moved on to the next interesting thing.