I've started a run dedicated to hunting down possible bugs, as well as trying to figure out the exact cause of this bug.
In this run, i managed to make the bug occur every single time i started the session before the area it happens in.
Attached to this post are two save files from that run and the manual save for both.
The unnamed save file starts before the setup for the bug, in -8/Materials.
The "Wastes" file is the save file closest to the bug happening, where the only thing required to witness the bug is to exit the Wastes and go to the western side of the Factory map to visually find one of the two Caves exits (they're both on that side, relatively close to each other).
I tested from that save file and from many other points; The only times the bug didn't occur was when starting the session in the post-Wastes -7/Factory. (Every time, i had previously identified the exit using access(branch).)
I know that this is a very low priority bug, but here's the savefiles anyway for whenever you want to investigate further.
If the bug somehow manages to not occur for you with those savefiles, then there's probably some difference between my Cogmind installation and yours. (I'm still playing on Linux through Proton.)