LoLz... declaration like this wont help. U need to show where your bitcoins are and sign a message from that address. Moreover, 500$ is less than 0.2 BTC right. Come up with at least 10+ BTC.
Also, what's the max. bet
25$
As I know, common max profit per bet on dice site is 1% of the bankroll. So if his bankroll is $500 then the max profit per bet should be $5 only, unless he has his own rule about it.
I have to doubt that people will be interested to invest on a new simple dice like this one. He needs to prove/show to people that it worths to invest on his dice site. But before that, he should build a good reputation first.