The fact there is real proof of you having the game hash's before you placed the winning bets should make the wins null and void in my own opinion regardless if you used the information or not. You were given an inside edge.
Yep, that pretty much sums it up. Plus StackGambler's answer to Quicksy's question earlier. I don't know if StackGambler actively solicited those hashes, but even if he received them "accidentally" or whatever the excuse was - the right thing to do would be to inform the site's admin and not continue playing.
A gambling site where the "dev" hands out seeds is not to be trusted either.