I think I was looking at the wrong thing when checking for electrical issues effecting the right flipper. I was looking for differences in voltage versus the left flipper but should have been looking for different measures of resistance.

The eos on the right flipper wasnt replaced when it was re-built ~ a month ago because it is a stacked type switch and the rebuild kit came with only simple eos switches in it.

I did clean the old switch with a file and alcohol, but maybe not aggressively enough.

Checking for a rise in resistance in the right flipper’s switch is probably a good next step.