As others have noted, U-S election law is not a factor here, but nevertheless I feel compelled to respond.

U-S elections are governed by the states. However, as far as I know this is the same nationwide:

Whether you voted is a matter of public record.

How you voted is not.

So the ballot itself is "secret", but whether you chose to cast the ballot is not a secret. Generally it requires some digging through public records to determine whether someone has voted, but once in a while you'll see a news article about some flag-waving candidate for office who upon further inspection has been discovered to have never actually bothered to cast a ballot.

Since there doesn't seem to be any mechanism for FTer's to see whether another member has voted in past elections, a member's non-participation in the current election could likely not be used against them should they decide to run for TalkBoard in the future.