You are really missing the point here bro and for one fact, winning is never guaranteed in gambling and for the fact that you were unlucky does not make the gambling site a scam.

If you win a huge amount of money and you refuse being paid, then probably you should report them as a scam but not from losing from a dice game that was stated as provably fair unless you just do not understand what that means at all. This is not about them lying or not, this is about you being pained for losing after expecting too much from gambling.