Hm. That doesn't match what I'm thinking of. Granted, I was a page during Rich's first years on the show, so I wasn't at every taping, but even as a fan, I don't remember any moment where Rich read a price in his script that gave away the answer to a game. (Although if that did happen, I can easily understand how it would get through rehearsal with no one noticing. The pricing games themselves were never rehearsed -- only the prizes were. So if a script page ended with "a prize worth $xx,xxx," everyone would just assume that that's what's supposed to be there.)
Because Roger can't remember the specific details, I'll just go ahead with the moment I remember. Maybe this is why he can't remember what game it happened in -- it wasn't in a pricing game.
During his warmup before an episode, Rich was chatting with the audience. I don't remember the context, but one of the audience members mentioned a Corvette, and for some reason, that prompted Rich to speculate on what Corvettes go for nowadays -- something like, "What would that be, $50,000 or so?"
The thing was, one of the showcases in that very episode had a Corvette as the big prize at the end. And even though Rich didn't have access to showcase totals, he had inadvertently made a pretty accurate estimate regarding the Corvette's price.
I hurried backstage to inform Roger (yes, you can call me a snitch), who decided that because everybody in the audience heard it (and we didn't know who would be in the Showcase round), the Corvette would stay. Needless to say, when the end of the show came around, the contestant put in a very good bid on that showcase and wound up winning the Corvette.
I was too low in the hierarchy to know whether there was any aftermath, but I can imagine Rich being told to never speculate on prices in front of the audience ever again.