Lowerdark rotlands rot tunnels... something hidden but not?

[SkagHunter]

At the end of the corridor just inside the formian hive, the lowerdark -rotlands-rot tunnels, there is a spot on the wall where it will make your character make the 'Something found' emote, yet nothing is there/ revealed by this

[VanillaPudding]

I want to say that is the "exit" to another area....I could be wrong though.