Saw the photos doing the rounds on the Facebook group and yes, something definitely looks off in that third corridor shot. The shape near the doorway has a defined edge that shadows dont normally have - proper sharp outline on the left side of it.
I'm fairly new to all this so I wont pretend I know exactly what I'm looking at, but I've been trying to learn about light contamination and lens artefacts and that thing doesn't look like either to me. The proportions are roughly human height as well which always makes me pay more attention.
Would love to see the RAW file if whoever took it is willing to share. Post-processing can do a lot of funny things but you can usually tell more from the unedited version. What camera setup were they using and what were the lighting conditions at the time?