I believe the technical term is ... "BUPKIS"
The coin room "Division League" is only really there to encourage people to play more, therefore spending more $$$. If you win your Diamond 1 group there is nothing more than the coin prize listed. There is nothing beyond that and in fact if you are in the Diamond 1 group for too long (something like 3-4 weeks in a row) you are automatically demoted to the group below Diamond 1.