After a few days of checking every foreseeable aspect of this case (email, private keys, synced browser passwords, secret questions and what not, seem to have been compromised at some point), we've come to the conclusion that the hacking extent is way to big to determine the ownership correctly so it will be better if the account remains locked indefinitely.
There is too much complexity in this case and since no one is willing to or can sign the message, the account will be locked forever.
So the James bond movie had a sad ending for everyone.
If legendster was true than he have lost his account. The hacker also jumped in the conversation, so if he was true, then he also lost his 500$ because he does not have an account for which he paid.