In my opinion

Royale enrollment should be everyone buying a ticket and each game has a max of 50. So, if 120 people buy a ticket then 100 people would make it into 2 different games. However, the casts would be randomized between all 120 people. If there’s 160 then it would be 3 games randomized between the 160 etc. To me this makes the most sense to avoid premades & keep the casts popping.