the TD can step in and force him to call, it has been known before. Irrc I read an article on this subject in a back edition on pokerplayer and thomas K said he had made someone call (the raise was ubber nominal) as it was on the bubble of a big event.

Having said that. If the guy is folding to everyone you can't say its chip dumping, just stupid play. Guess it falls to the TD to decide