Sooo my thoughts.
Maybe #2 is going lean?
Clogged injector?
Maybe an air leak in the intake tube, also leaning out the mixture?
What did the EGT show for that cylinder?
A bit of a long shot, but you could have a spark plug with a cracked insulator causing detonation. That would raise CHT and Oil both.. Cirrus and Champion went back and forth recently about cracked plugs causing total engine failure, but those were turbo'd. Think what you want, but I personally saw a cracked plug and a Cirrus with a hole in the piston. Just
sayin Champions position on it can be found here:
You are correct though, could be a probe, and swapping would be the quickest check that I can think of.
Hey! I just noticed who this is. haha Should have just emailed direct, oh well, already done. Let me know if I can help.
Tom McNerney