I know that quite a few of these are currently hold in European zoos and even on the private sector. Thouse held privatly on Europe are the result of a captive breeding event that took place in 1994 if Im not mistaken, in a German zoo and were allowed to be traded legaly. I think they were sold by the equivalent of 1000 euros each, not bad at all for so rare animals. Some of the now adult animals are kept in groups in the hopes they will breed again. That will provide a safety net in the case something happens to wild populations. Unfornatly the same was not yet acomplished will hellbenders. Thouse are few and far between and it seems zoos are more worryed about keeping their prize specimens then they are in getting them all together in the hope of breeding.