[SiriusHardware]

Slightly confusing because you have done half of them to +5V and half to 0V, unless I am misunderstanding your results. To clarify:

Measure from +5V (red lead on +5V) to each of

UI10 pins 8-9
UI10 pins 6-7
UI10 pins 4-5
UI10 pins 2-3
UI11 pins 8-9
UI11 pins 6-7
UI11 pins 4-5
UI11 pins 2-3

And report the results, then measure from 0V (black lead on 0V) to each of

UI10 pins 8-9
UI10 pins 6-7
UI10 pins 4-5
UI10 pins 2-3
UI11 pins 8-9
UI11 pins 6-7
UI11 pins 4-5
UI11 pins 2-3

..and report the results.

Regardless of what you find, could you please also do the scope comparison between these eight pin pairs as well. Doesn't have to be tonight, take your time.