Given the state this took place in, the pamphlet above and how directly the event is associated with the Peppermill Reno, and the fact it was a "gaming" style of event with a buy-in and prize pool I would think that the Peppermill would very much NOT like a group of people sending the information of what took place to the Nevada State Gaming Control Board.
This was a gaming event, it was partly sponsered by, and took place in a casino with a gaming license. Gaming licenses are VERY strict and have extremely precise regulations in the State of Nevada. If a large group of people were to send complaints into the Nevada State Gaming Control Board
http://gaming.nv.gov/
And the Peppermill were even threatened with an investigation over the matter I am guessing the pressure Tony would suddenly be receiving would be a little more serious and he would be paying up. Or the Peppermill would to make the matter go away. One thing is for certain, if this WAS to take place Tony's name would be on the books in Nevada and it is doubtful any casino in the whole state, and possibly the entire country would do any business with him whatsoever.
I am not owed money, but I am pretty sure a gaming event like this with a buy-in, a prize pool, and taking place within a well known Reno casino with a gaming license from the State of Nevada has certain regulations and guidelines that must be followed, and guarenteeing winnings are properly paid out in a gaming related event would be right up there.
Put the pressure there. if they take the matter seriously it will in turn put very unwanted pressure on the Peppermill, and Tony will suddenly be getting a whole different kind of pressure that will likely get that "slow to react or care" attitude adjusted.
The gaming control board is NOT going to take kindly to an event in a licensed Nevada casino not paying off thousands of dollars owed to dozens of patrons of an event held within, and sponsered by the casino.