Hope the shade will help your plants Erica.
I also grow my succulents outdoors, but all in containers. During this recent heat wave, I had to adjust my watering, I did everyday watering before the sun hits the plants. Usually I also do intervals in watering, but this time around, we had really dismal rainfall during Spring and this heat wave was just hot and stressful for my plants, I see some stems bending already, so adjusted the watering. My plants get part sun in the morning, some full sun till noon and shade again in the afternoon. Ambient-wise the temps during our heat wave went to 109F at times, though still cooler compared to your temps. From what I have seen temps over 100F really takes a toll on them.
From your photos where you show the wilting stem..it somehow reminds me of some succulents that are either in heat stress, or could be succulents that go monocarpic and die after it blooms, or it can also be trying to conserve its succulence and energy by focusing its growth to a few stems, and with the heat they go semi-dormant. You can try and get cuttings and grow them indoors for now to save your plant if it continues to go downhill.
Good luck! Hope to see updates later on! Our heat wave has ended so back to our high 90's and at times windy, will again adjust my watering to intervals.
