It seems we need to be clear (assumedly, only if true) that in 197x, Kerry received, e.g., an "Other Than Honorable Discharge, (e.g.) which only through Democrat President Carter, contemporaneously with his draft dodger and AWOL amnesty program" was done this favor from his party's comrade, the President.
What becomes important is the reason for such OTH discharge. If it was stated anywhere that "he gave aid and comfort to the enemy," the man is simply ineligible to be President, and must be removed from the ballot, even if after the fact.
HF
This is where my knowledge gives out. Is that a bright-line rule? If so, I agree that's the bottom line.