I believe this will take time. I would be patient since it may be that he is trying to make some arbitrage profit to pay us back. I understand it as long as he is trying to do things right. I have two users in btc-arbs: "hongo" and "viru". Add "hongo" to the fully refunded (without earning) list and "viru" to the not yet refunded. I have surrendered my earnings since I prefer to have my money back than nothing. If all this story (the hacking and the arbitrage) is true and if I were in your place I would do my part to help out and surrender the earnings too. In that way more people will have the chance to be refunded but you probably need to say this explicitly.