Whoa, might not be out of the woods yet, need to be thourough, thats 3 neutral to ground connections that could explain current on the ground, but NOT the HIGHER, or LOWER voltages.
When you have a 120/208, or for that matter any system other than just plain vanilia 120, and you get a higher voltage to ground than what is input to it, that voltage, that higher voltage has to come from somewhere. In a high/low voltage scenaio, Phase A and Phase B (Or C) can borrow and steal from each other... One goes up, 1-2 two down, et cetera. The "real" neutral point can "float" between loads. Depending solely on which might have more load than the other at the time. A set of voltages read fluctuating like 140, 100, 90 would mean the balance point of the load is not held in check at one point by solid grounding. Was this High/Low problem on one of the circuits you just described and limited to them or it alone? If this High/Low problem was panel wide, or service wide, it sounds like there is still a problem.....
