I cannot win the dice rolling game for the life of me :(
Is there some sort of trick to it
It is very hard! It centers around predicting your opponent's moves and making the moves which will counter them.
The Pokemon do not move randomly, and they all play the game a little differently! As a hint, I think Rhydon plays the game more naively, and will throw 2s on their turn and 1s on yours! So you can beat them if you anticipate this and throw 0s to slow them down, or aim for the shortcut by anticipating their throws.
All of the Pokemon are a little different though! Learning their patterns is a part of being good at the dice game. It is hard and the rewards are not too big -- so I hope you'll just enjoy the game even if you don't win at it. The Pokemon are happy when they win 😀