When they aired the Woolery "Wheel" ep. during Merv's tribute, was that from someone on the trading circuit? Don't know why I'm leaning towards that idea, but it's definitely plausible I suppose.
As for the tribute, there's no need to go through all that trouble when you have eps. available where he played the game. Despite her revival of popularity, a lack of Betty White is not a big deal, because quite frankly the tribute's not about her. There's no reason why they can't dig up the 10/20K shows though. They could honestly do a tribute for a few hours, with a couple of eps. from those and the 25/100K versions.