I just remembered that they touted Billy Crystal's appearance on All-Star Secrets in June 1979 as his first game show appearance, when he had been previously been on two different weeks of The $20,000 Pyramid, one of which aired on GSN in the past. But like Brandon said, "who cares".
Frankly, I do, and I don't begrudge others who care as well. I don't like that we've gotten so lax as a society that we can just state "facts" and not worry about whether they're true. (And I'm not even talking about political ads, which are a different issue entirely.) If GSN is calling these appearances "first" and they're not, that's simply wrong, and shouldn't happen. There are plenty of amateur historians, including at least two I know that work for the company, who could set them straight, plus I imagine IMDB has it right. GSN either knew they were wrong and didn't care, since most of their audience wouldn't know, or they were lazy and didn't check. Either way. it makes me think less of them.
/Not as much, though as when I see the banners saying that more Family Feud's (yes, apostrophe 's') are coming up.