Hmm, I don't really understand what's actually going on. Are you closing the door while abom is standing in the doorway, causing the gates to lock/freeze him in position? Once the doors are closed, they should (i believe) squeeze him out and push him to a nearby (walkable) tile. If my assumption is wrong, could you provide a screenshot of the bug in particular?
The main purpose of those gates there is to exploit them as much as possible, in order to defeat the Abomination.
