I'll try to answer your question, the slot above his thumb is where the door stricker slots into. The stricker is attached the a-pillar with three or four bolts. The lever you see further up in the picture is attached to a push-pull rod that is attached to the outside door handle (pull handle). When the handle is pulled, the arm moves down and releases the latch that is wrapped around the stricker. Most likley in your case the spring has broken through the plastic housing and will not allow the internal latch to release from the stricker. You have to get at the inside door and remove the entire unit. Hope this makes sense?