If someone actually win at your site, it doesnt always means that the person actually doing a fraud way to win, if you are the admin of the site, you can easily verify this by looking at his previous game and determine if he indeed had used a fraud way to win, The house doesnt always win
I paid couple players, there is no problem with winners. There is problem ONLY with this specific guy which was ruining house. I already paid him before thinking that its statistical coincidence.