Monumental (half) marathon waitlist

Hello, I’m traveling to Indianapolis the weekend of the monumental marathon and thought I’d run the half while I was there, only to see it’s sold out. I can pay something like $120 to get on the waitlist, but I don’t know if that’s just sending CNO a free gift or if I actually stand a good chance of getting in. Does anyone have experience with the waitlist? Should I just get a 5k entry while I still can, or am I likely to get in on the half marathon waitlist?