it's hard to describe but it's the right bottom side of the wall in the room with a ton of small cogs that spin and a teleport ghost going back and forth on the bottom half of the screen
I just spammed teleport a lot and one of them happened to teleport me there, I think I maybe teleported on the cog that's spinning and it moved me slightly outside of the wall for just a moment and then I teleported again immediately and the ghost went inside the wall, but this is speculation on my part, only thing that was special was me teleporting in rapid succession a lot and it just happened by accident