I didn't see the "expensive" items, so I can't say anything about that. But if I read the story correctly, the money wasn't found in his room, so there's no proof that it's his. And since his roommate is being charged with dealing and not DJK, it's not hard to make the argument that it wasn't DJ's money.
Though I admit that's pretty naive. I hope it's not his.
Regardless, he made the choice of allowing this activity to take place under his roof. He didn't have to abuse drugs, live in a place they were being sold, etc... This isn't a case of a person making an immature decision to try a drug, this is well beyond that. I think it's pretty naive to assume he had no responsibility for the actions taking place under his roof.