Hiya Hiking,
I agree with Bill (which I have noticed we tend to do quite often. . . )
Absolutely do not let the heat deter you. There will be plenty of superb and shady camp sites to pick from. I'd suggest when you get there, you set your pack down and spend 15 - 30 min just exploring to find the best spot. We took something right away and were too lazy to move after we noticed some really top notch spots right on the river!
Drink lots of water, take long rests, plan on a longer lunch during the heat of the day and you'll be fine. Pate Valley was still very warm, but cooled off nicely in the evening. PV was just really really pleasant. Lots of lush trees, absolutely pristine clear river water and often a refreshing breeze.
The heat will be something you simply put up with to be in one of the most beautiful places on the planet. Think of it like mosquitoes.