Hi aupanner.
Thanks for a really interesting post.
You seem to have pretty much ironed out the main logical issues / questions.
I tried to find out the floc and wax point of the oil last night.
But drew a blank!
One question is what oil was used before? The emkarate Oil used is a POE.
So what went before is really relevant as you state.

Have you considered a power element failure on the Expansion valve?
Although we have our own Danfoss gurus who may be able to add to that.
I would of questioned the fans also but you have that covered.
Good luck on this one its interesting.
Thanks Grizzly