Thermador C272 double wall oven

Following a self clean cycle of the lower oven, which went fine, oven made clicking noises repeatedly as it cooled down. After many hours and fully cool, it still wouldn't unlock the door. So I got the door open by moving the latch tongue with a wire hanger. The latch is stuck in the lock position (to the right).

Question #1: Is there a way to remove the latch assembly without taking out the whole upper oven interior? If not, how does the upper oven interior come out?

Question #2: Is the thermostat next to the latch normally open or closed? I think I can get to its terminals with multimeter probes to test. I did push the red button as best I could with a screwdriver tip from the side, but didn't hear it pop.

I can post a picture if necessary. Thank you for any help.