Hi, it's strictly forbidden to use payment methods registered to someone else on your casino account. In this case, your friends broke the terms and conditions. If they won the jackpot, I'd be quite sure they wouldn't get the winnings, but that's another case.
I suppose they don't want to pay you since they presume you have multiple accounts in the casino (based on the common payment method, you probably played from the same location, same IP address etc.)
I'd say the question is if they're also willing to believe your story about the poker night or not. If your friends have a casino account that they've been using for months or years, they normally use their payment methods there and this was just an exception, then they could believe it. If the accounts are new, then I'm afraid the casino will believe all of the accounts are yours.
