Wow this place is just as brutal as bitcoin itself, or more. Actually I once accidentally sent bitcoins to someone and they sent them back.
The email used contains my real name. I use the same name and the alias 'TERA' at Bitfinex. I also have a Facebook account and a youtube account, and a TradingView account where I have posted charts/videos at the same time as they appeared on this account.
The hacker says he is not a US citizen. You can clearly see from my history that I am a US citizen.
If you take a look at the stickies, it says that you can prove that you own the account by alternative ways but there is a high chance that it would not be recoveres especially if it takes a lot of time to validate it. Since you have no other choice then better give it a shot.
One more thing, have you posted any Ethereum address or been in a spreadsheet? You can try that. Just attach the link and sign a message with that address.