That does seem to confirm it then.
So which kind of fix are you more comfortable with?
Opening up the pedals is tedious, but not difficult, I prefer dismantling them this way so the wiring doesn't get disturbed:
Once apart, you could unscrew and remove the ground connection from each pedal. The screws could go back in place to avoid losing them. Wrap the tags to the wire with electrical tape to stop them touching the metal again. The ground tag is circled in green:
View attachment 648918
Since the pedals will be grounded through the rig this should work fine. (Using some grip washers would help bite into the rig a touch to make sure the connection is good).
Otherwise, I dunno what the best/easiest way to isolate them would be. It depends on how much space there is around the bolts in the mounting holes of your rig. If there's enough to wrap part of the bolt in electrical tape, then that plus some plastic washers ought to do it, although there's still a small risk that the tape wears through and it connects again.