I am not saying you are a scam. I am also not saying that you are cheating. I could believe that you are honest. But provably fair is not about believing or trusting.
Provably fair is a way for the players to verify and prove if they have been cheated or not. On your site, they cannot verify and prove this, because using "timestamp" is unreliable as shown in my previous posts. Therefor the player just has to trust you to be fair.
That is "trust us, we are fair" and not "provably (=you can prove we are) fair".