It is ridiculous that owner of this gambling site has negative trust.
It is pure abuse of the trust system to give negative trust for this as this is very clearly a gambling game and they don't claim anywhere that they would invest users money to make profit or that there would be guaranteed profit so this is not a fraudulent investment operation which is definition of ponzi scam.
They could as well be red trusting Stunna because people can lose money with dice game too...