if you have connection to disappear in this world, then withdraw the money in cash and disappear.
if you have no idea, how to disappear, no contact, better give the money back to the bank.
now, he cannot use his passport anywhere in the world, you got to make new passport, and change his hair color , hair style and everything. like a mini plastic surgery . then he have to make sure his white gf does not miss home and family and call back to NZ. that will be the end.