Tom Dreesen (who I've seen so long as Frank
Sinatra's opening act I can't see him hosting a "hip" show)
Jay Leno. This is the first time I've heard of this, as well as of Leno auditioning to host a game show of any kind. He was becoming one of the bigger names in standup comedy around that time, and his style wasn't as predictable as his later "Tonight Show" work, so I'm curious how he would have done as an emcee.
Dressen and Leno were two of the main names features in the book
I'm Dying Up Here (the same one that spawned the current Showtime TV series) about the standup comedy scene in the late 1970s. Dressen had just split up with partner Tim Reid and was working The Comedy Store, as were Leno, David Letterman, Richard Lewis, Elayne Boosler, Alison Angrim, and a host of others.
The book deals mostly with the problems of the comics unionizing to get reasonable pay in 1979, and the comics subsequently holding a job action. Almost every name comic was pro-"union" (Garry Shandling was a notable exception), and The Comedy Store finally settled with the striking comics after one of the anti-union comics narrowly missed hitting Jay Leno with a car (Leno slapped the side of the car as it went by and faked being hit). Dressen was the ringleader (he had come from a union household, so knew a bit more about organizing), and stopped playing The Comedy Store upon the suicide of fellow striker Steve Lubetkin, who was denied gigs at the club after the job action ended.
It's a great book.