You're right. Aproud is the seller who sold it to the guy who traded it to the guy who sold it to the guy who claims their are issues, unless I'm misunderstanding something. Owner number three in this situation is the only responsible party, IMO.
I see, yes, you're right, there were a total of four participants. I was confused. I still think it's fishy... and I agree that you can't go back "x" number of sellers expecting to undo multiple changing of hands.