i'm not on-site but someone who enters an MTT with one of the cheats should call the floor over and let them know you want something done regarding known cheats being allowed to gamble on the property. tell the floor if you don't get a resolution you'll contact the Nevada Gaming Control Board and file a complaint. the Board doesn't take kindly to patrons feeling they are being cheated in the state of Nevada.
here's the Board's contact info:
https://gaming.nv.gov/index.aspx?page=24
believe me, Jack Effel doesn't want anything to do with the Board snooping around his business and worrying his bosses (not to mention the potential heat and bad PR hit for Caesars Entertainment).
this is the course of action that has a chance of delivering results.