All he needs to do is tell the guards that he is an effective altruist and how, despite appearances, everything he did was for the greater good. They will let him out promptly.
"Your toilet is your stair machine, it's your bench, it's, uh... your fridge, it's your... ( Chuckles ) ... lover, it's... it's... it's your brother, it's your priest. Oh, and also, most importantly, it's also your... toilet."