It is a pretty robust little item with no moving parts aside from the pointer linked to the bimetallic coil. I am guessing when I say that it probably just came loose and fell into the cockpit, annoying but so what?
No joke, you really could just slide the window open and stick the probe out into the passing breeze if you even cared to. The temperature inside, in flight, is going to be pretty close to the temperature outside in any case, given that your average Twotter is about as drafty as an old shed.