They have and will continue to deny it, understandably, but I was paid out with a counterfeit $20 here.
I live outside the US, pulled out money when I got to the poker room, and had 0 cash transactions outside of it the entire weekend -- that I am SURE of. Bought in and cashed out probably 8-10 times. The last time I tried to buy in, I was called over by the manager and head of security to be humiliated when they caught their own fake bill in the machine. Either an employee's scamming or their equipment is faulty.
Now I'm in a Secret Service database. Play at your own risk.