I hate being repetitive, but there is just no logical reason for a hole to be in that specific place above the fixture. A fixture sinking that little wouldn't expose a hole like that. Poor maintenance makes sense for a sink faucet handle to be loose, a hand dryer to not work, or a bathroom stall door to be falling off. A hole in a wall above the top of the toilet fixture doesn't make sense without some assistance in removing material from the board behind the tile. There is no hole in that area that would be exposed if a fixture sank an inch. If it sank several inches, perhaps the hole for the water supply might become exposed, but that's just not the case based on the video.