Yes i also think that markets don't need so big price like that , bitcoin good price is 3-6k for now . 12k is to much to get moving again to 20k . We need cheap price and a lot of new money and investors to come back here to starting to buy bitcoin again . Also we need get hype back , nobody talk about bitcoin now on TV like before January when every day on TV talking about Crypto and investing in that.
BTW ? Why Mt Gox Needed to Dump the price ?
Yeah, I'm also questioning his intentions of dumping his huge amount of bitcoin as this very critical times. Although it has been reported that he is doing this for several months now so it makes sense that he is the one to blame for all this wild price swings and correction that we are seeing.
But as far as the OP's questions, I don't think that we can just delete their wallet. Crypto and bitcoin is decentralizes and no central authority to control and manage the cryptosphere.
The best thing to do is advise the guy not to dump it or go OTC and even do a public auctions of the trusted bitcoins on him.