Oh no! We're so sorry you ran into this, we'll make note of this and try look into it as soon as we can. In the meantime, you can press Right Shift + Home and it will reset the scene which should hopefully fix the issue for now. Thanks so much for letting us know :)
I've had that problem happen and I placed Morton down, which seemed to have locked the movement of my character. I was able to exit the place using Right Shift + Home. Since then, he is nowhere to be found and I can't continue the quest. I still can't find anything when I go in the stump, even after resetting the scene.