Here's the thing about Moab, it's gonna be hot when you are there, no way around that. The RV park you've chosen is kind of newer so there is not a whole lot of shade. My first recommendation for full-hookup RV parks would be Archview, but again, it is newer so the trees are not big shade trees. The RV park in Moab that has big shade trees is Slickrock Campground. But understand that Slickrock Campground is older, has gravel roads and spots and is probably not as nice as the newer RV parks. But, I've never had an issue staying there, prices are reasonable and there are lots of shaded spots.
One other recommendation while you're in Moab, consider doing the https://www.xtreme4x4tours.com/ 3 hour evening tour. It is not cheap but is by far, the best 4x4 tour you can do there. The guy goes up and over some amazing stuff on Hell's Revenge trail that no other tour does because they are unable to do it. It is completely safe and everyone, even my wife enjoyed it and she doesn't generally like that kind of stuff. This is coming from someone who goes to Moab to ATV ride advanced trails out there.