If the hacker does not return the 80 BTC, it seems there are two options:

try to collect 80 BTC and return them to the XCP buyers who's funds were stolen,

try to collect 35,000 XCP and give them to the XCP buyers, instead


It seems the XCP route is perhaps better? I feel the community could come up with 35K XCP, but I have a hard time imagining 80 BTC. Also, the buyers wanted XCP, we know that because they had buy orders, and giving them XCP keeps them in the community so to speak.