Do I get it right that the goal is to be the last player to cash out right before the game "crash"?
What would prevent the site owner to play himself, since he knows the gameCrashAmount and could act as a lucky winning player (effectively a shill)?

If that is possible, then the game is only "provably not changing results", but not provably fair.
The owner could win abritrary high gains (possibly choosing to remain within a realistic variance).

Maybe I misunderstood how the game works... Please comment.