The game is in fact provably fair.
Before a game is started, you can see the "secret hash" at the bottom of the page. After you have finished it, the "Game Code" (consisting of your game ID and bomb locations) will be revealed. You can check the sha256 digest of the "Game Code" to see if it matches with the "secret hash".
Please don't tell me about hash and SHA256. Now days every gambling site uses secret hash that does not mean they are fair. Hashes can also be manipulated, its just user does not know and loses.
Do you have any proof that proves hashes can't be manipulated at all?
With a provably fair system, it doesn't stop a site from scamming. But whenever the site manipulates the game result, players can notice it and prove it.
SHA-2 has been thoroughly analyzed by worldwide cryptographers for over a decade, and still there is no known case for collision. I don't think Coin-sweeper owner is able to find another plaintext that will hash to the same "secret hash".
If that would be the case none of the gambling site would have survived.