We had a small fire inside our microwave and now nothing works. No display, nothing.

I read this thread on a similar GE model, but the P/N suggested there doesn't seem to correspond to mine. That thread recomended replacing the 'cavity thermostat', but there is nothing called that in the diagram for mine. There are three different items called 'thermostat', but I'm not sure which, if any, is the one I should be looking at.

The fire was on the left of the cavity, below a grille in the top of the cavity. The 'sensor-gas', item #51 on the diagram, is behind that grille. I initially thought that was likely the thermostat in question, but it doesn't seem like it.

Can anyone point me in the right direction as to what I ought to test and how to test it?

Pulled it off the wall so I could check thermostat #3. Found it had continuity. So, for the two with continuity I unplugged them one at a time and plugged the MW in to see if removing the continuity changed anything. It did not. I placed a jumper wire on the one without continuity and all that did was turn the vent fan on, no control panel or anything else.

Looking around up top by that 'gas sensor', I discovered what looks like another thermostat, in the same location as that other thread mentioned in the first post. It's not listed as a 'thermostat' in the parts list, in fact I can't find it on the diagram at all. It tested no continuity and when I jumpered the wired the MW came back on. Now I just need to figure out what it is so I can order one.