Party poker closed my account. Can I sue if decision is not reversed?

[DarthHate]

Here's the story:
Exactly a month ago, a friend asked for 1.8k on stars. I said ok, pay me on party. he deposited using his g/fs card and sent me the money. I had already deposited 2k from my own credit card by that point. I withdrew 1k temporarily for rent and expenses. Next day my account is closed and support quoted "fraudulent activity" in the email.


I called them and explained the situation. They asked that I mail them the usual passport/id credit card front, back and complete and sign a form authorizing all withdrawals etc. I did so. They then emailed saying that the 2k i deposited was deemed too much compared to my wagering (i was playing 200NL). I explained that in 200Nl there are swings, bankroll management, etc (FFS!). They then asked for a bank statement. I eventually sent it (i had some issues to sort out that had priority) and now, 3 days later they send me an email basically saying that after a thorough investigation of my account they deem that i was trying to defraud their cashier system and use it for my own benefits.
The 1000$ that the dude transfered weren't withdrawn and party said at the start that they'd give it back to him. He's told me that he has sent all the documents they requested and has put his g/f on the phone with them to tell them that him depositing with her c/c is fine. ( I DO trust this guy and am 100% sure he's not lying).

I've still got 1600$ in the account and basically I will call them again tomorrow. As an aside, everytime I talked to them they said that after I send the documents everything will be ok.

If they still decide to close my account. Do I have a leg to stand on to sue?