I FOUND IT! Look here!! I have struggled with this other memory on my wife’s iPhone for four months. We always thought it was pictures, iCloud storage, texts, etc… Today I sat down for several hours looking through and isolating apps after restore. YOU’LL NEVER BELIEVE IT- A SleepWatch tracking app was taking up 35 GB of memory! Idk why it really doesn't show up in ' iPhone storage ' when you open the app but there it is! I have attached a photo for reference or proof. If you are having this problem it has to be an application on your phone tracking too much detail. With a little process of elimination, you can find.