That's some typical scamming scheme of gambling sites, sometimes deleting all information before doing it so the users won't be able to have any evidences. I think you should move this to scam accusation even though it's gambling related, I think you should try to inform them too on their ANN thread about the situation and for people to be careful on the site while your issue with the Bitdice is not yet fixed.
Here's the ANN thread of Bitdice:
https://bitcointalk.org/index.php?topic=5304279We have had and will not have problems paying users who have won fair and square. However, in this kind of a case it's a bit of a grey area. He attempted to scam for which he got banned. If he returned that 0.04 ETH he didn't pay back, obviously there wouldn't be an issue processing any and all withdrawals but we all know that won't happen.