Can't address Demotte, since I've not stayed there. But was at the North Rim the last week of their operation before closing for the season. There were a number of larger Class A rigs there, interspersed around the CG. They are all pull thru sites there, I would recommend one of the sites on the outer side of the loops vs the inner loop. Had site #10, was plenty of room for my 26ft trailer (30 ft w/rear slider) and my GMC 3500 dually, with space left over. The "prime" spots are #11 through #16, which are right near the canyon edge.
In addition to the CG being convenient to the Lodge, there's also a general store and fuel there at the CG. However, fuel is not cheap. Would be better served to fuel up just outside the entrance, at the Kaibab General Store. Diesel fuel was 30 cents/gallon cheaper there.
2007 GMC Sierra SLE 3500HD Dually
2016 Coachmen Catalina Legacy Edition 243RBS
2007 Keystone Outback 25RSS - R.I.P.