Although I don't know exactly how it works, but one way to obtain the information could be to target the hosting company with a court order for information disclosure.
Good option. Another option would be to hire a group of ethical hackers who could work along with the cops in order to disclose crucial details related to this website which could shut them down completely.
Maybe those that do business legally and do not hide their owners' identities?
@Desmong basically admitted that 1xbit scams their players and the irony is that 1xbit is actually paying him to help promote their site in this forum. Hilarious.