Does the timing stepper motor assembly on the passenger side of the pump look ok, connector plugged in? You could also disconnect the timing stepper motor's mechanical linkage, and then try to rotate the mechanism on the pump by hand to see if the cross shaft moves ok.

How'd you rotate the engine to allow access to the 3 pump gear bolts?

I saw some blow-by in the second video that seems out of the ordinary (coming out of the valve cover where the CDR is normally located), though it wouldn't necessarily have a bearing on your current injection pump problem.

Jim