I want to make sure I'm not masking a potentially worsening problem by either an electric ground or an earth ground.
Although I'm not totally confident of the GFCI on the pedestal, I plugged into it (with the ground intact) and ran a couple of loads. Nothing tripped.
Back on 50A (with ground intact), I measured current from the frame at 0.7mA.
I think introduced the open ground (30A) during which I measure just shy of 4mA current. Interestingly, the voltage (with the main breaker of the distribution center on) was back up to 57V. Random?