It occurs about 50 to 70% of the time when you select Random, join a MPC game. It does not occur 100% of the time, so there is no sure fire way to recreate it. But, it occurs often enough that if you select Random, MPC, and it's YOUR game and someone joins, edits clubs and is green, you will not have a wager box given to you. And no, it obviously never occurs if you set the game up. Your solution to the problem, if you recall, was to always set up the games, but this logic is flawed, because if no one is selecting Random, to join a game, unless you invite someone specifically, you would never have an opponent.
Just look at the programming, when you first introduced MPC and it worked all the time, and compare it to today, when it seldom works and see what the difference is?