Can't you even care to get the private keys of few of the addresses holding 5BTC? If you do this, I am sure people would feel more safe to play on your website. Its good for your business and if you are denying to sign a message with cold wallet addresses then surely there is something fishy about it.
No. I do not want to get something from these cold wallets before it is necessary. No player on our site can claim that he did not get any withdrawal.
I have no clue about the previous stuff about this site .But the current bet listings are more than enough for me to not play on this platform .There are hardly any players who are in green meaning winning .Most of the players are in the loss (red).Don't think how accurate the stats are but they surely are accurate enough for me to convey NOT to put my money here . 
That are not so many bets... Do not know what bets exactly you mean, but at the moment, someone bets: Player_754. I do not know who this is, of course, but if this is someone who writes here also, he can confirm that he won. There are not so many negative bets for now... Provably fair and 0% house edge does not mean that you win always
EDIT: Just tried to figure out what bets where shown at 01:21:26 PM... There were also positive bets. Around 50%...