I would guess that other Favia/Goni is stinging the crap out of it at night. I’ve had many instances where one coral was stinging another and despite looking each night, multiple time per night, and never actually caught, but as soon as I moved one of them, they started to recover. I am willing to bet it’s not the pods. Something else is killing it, whether it’s another coral, fish, or water quality (IME when people say ‘my water is fine’ that’s usually a red flag, and even if it is ‘fine’, by having another set of eyes look at your test results, they may see something you don’t). Since the missing tissue is all on that one side, I’m pretty positive that it’s the other Favia/Goni that’s doing it. Favias/Goniastraea/Favites don’t all get along, I would put a few more inches between them.
Edit: You can see the coral above has some sweeper tentacles out, it is undoubtedly the culprit.