We used a similar service in Idaho last year.
We were trying to find a campsite close to the Silverwood amusement park in August, and everything we looked at was fully booked. About two weeks before our vacation date, I got an email that said Farragut State Park had an opening for the time we wanted. I jumped on it right away, was able to book a site with full hookups, and we had a great time!
Retired US Air Force, aircraft mechanic (A&P), truck driver.
2015 Thor Citation Sprinter.