Unfortunately, that doesn't work with hotels. As happens every year around major events, people learn that this is a huge gap in consumer laws. Many people will find, around the Super Bowl, the Indy 500, and other major events, their reservations are simply cancelled and all they ever get is a shrug.

While I personally believe that once a room is rented under a set of t&c, those must be honored (as DOT post-purchase rules require), regrettably they don't.

Unless you are very certain of the result, I would not get into an email back-and-forth with the GM. You may simply find your reservation gone. And you may find that nothing ever comes of your complaint.

If you are dead set against providing a guarantee, call the guy and tell him your concern. If he won't budge, you have a decision to make. Don't provide the guarantee, lose the room, and maybe he gets a nasty letter from his AG, but you watch on TV vs. give him the CC #, and enjoy the race.

It's shoddy because it's not as though this date isn't pretty well known out there, but it's the world you are stuck with.