I have many azaleas and never saw damage like that . Possibly lack of water. However, azaleas love acid soil and your concrete planters imply alkaline soil. Checking soil pH would not be a bad idea. What I do is take a soil sample ,mix it in distilled water , and let it settle , then use aquarium pH test kit ( methyl blue or bromthymol blue , I forget). Or garden shops may do the test. I would leave your plants for now and give them time to leaf out. I have trimmed dead looking camellia branches more than once only to find they are still green and may have grown.