The replay lasted 10 minutes but no decision had been made yet, so I never heard the reason for the scratching, it almost had to be for broken equipment. As for the bettors who thought they had the exacta and trifecta, you're right, they got screwed. If the horse indeed had broken equipment before the start, I'm guessing the driver wasn't aware of it. Once a horse is programmed to race even if he's a late scratch, I believe the claim is still valid.