The prohibition was not against running for office, it was for WINNING an election (something some here allege he could not do) and being seated. If Davis never ran for office, or never won, then he had not been penalized by the 14th.
Considering Davis was in jail, it seems unlikely that he would be in any position to run for office. Furthermore, the penalty for treason is DEATH, Which would prevent Davis from ever running for office.
Chase's dubious reasoning was an escape clause for morons to grab hold off, a specious line of reasoning that allowed the US Government to abandon a case it could never win.
Almost as dubious as your reasoning. The amendment said that he could not hold any office, not just elective office. That would include cabinet and senate, as well as House and state and local offices. Whether or not he ever planned to run for office again was irrelevant. He was prevented from holding almost any office whatsoever because of his actions in leading the rebellion against the United States. He had been punsihed for those activities. Call it what you will, Chase's reasoning concerning the 5th Amendment was sound and it saved the U.S. from a divisive trial and conviction of Davis. In the end perhaps it was an excuse to drop the whole matter and get on with the task of putting the southern rebellion behind us, but to call it invalid or bogus is wrong.
I been TRYING to explain that EXACT point to NS for several threads....I've been knockin , but NOBODY's home! :)