I called and the phone number is not active that is listed. Do we need a reservation to camp?

Sometimes the phone service goes out...when that happens you can contact through FB

Rv with hook ups or cabins definitely call for reservations. Primative camping or generator camping depends on event weekend or not. They are on Facebook try to message or numbers there

If it's and RV hookup, yes. But they are booked about a year out always. They usually have plenty of primitive camping, if you have a generator with RV you should be just fine.