I have received a reply from
legal@rollbit.com after taking Razer's advice to e-mail them for more information, obviously nothing productive once again.
I asked them who is investigating me and what the reasoning is.

looks there is not much that can be done other than wait. them not saying who is investigation you is probably part of their protocol(though I am not completely sure).
anyway, you mentioned that losing this money doesn't hurt you but instead of just giving up wouldn't it be better to just wait and see the result of their investigation, I mean, it wouldn't hurt waiting for their investigation to finish.