I honestly think there is a pretty simple way Disney could stop a ton of the cheating...
Disney 100% follows these Facebook groups and reads threads like these. They pretty easily can target a few high profile cheaters. Simply get irrefutable proof they are lying, such as video evidence that a couple split up right before a ride and claimed they were traveling solo to get this advantage. After the ride, permanently ban the couple from WDW. Do this a dozen times and a lot of people won't risk lying.
Put a team of 10 security people on it for a month and watch the abuse drop.