This happened twice in my plays today. One in Athel Yenlui, the other in Into the Nest.
granted it doesn’t happen often, but I was able to replicate the bug by aiming Battle Wizard ult at the bugged spot.
In Into the Nest this happens at the third tome area, after the drop point from the previous area, beside the chest that spawns at drop point.
I was able to replicate this by searching the area with Battle Wizard’s firewalk casting circle. When I cast the circle around the area I took a screenshot of, I was able to fit the firewalk between the wall and rock. The screenshot above shows the result when I casted firewalk.
I have tried finding the bugged spot in Athel Yenlui, but I couldn’t find exactly where this had happened. It was after the first grim, and it happened the same way like the one in Into the Nest. By chance, I had firewalked inside two objects that teleported me under the map.