They indeed do have something in common. The crankshaft turning in the injection pump is it. I would rather see you not get into the injection pump yet.

The diffinative test is to find out if the lobe that powers the lift pump is turning when the engine is rotating. Your simplest approach to this might be to remove the lift pump. There are other ways but that one has less potential of things going wrong in any way. Plus it is a pretty conclusive test.

Glad to hear you had someone else crank the engine by the way. Seems you did follow the limited protocals of the test so all is good so far. By and large though the injection pump does have an issue of some sort at least is proven as far as I am concerned. You are closing in on the target now. Lets see if that crank is turning in the injection pump first or not though. If not it is an unusual failure but still a possible one.