Well, that was unfortunate.
I think I'm going to have to disagree with Galzria here, especially in a RMM game. There can be unknown roles that impact vote-counts, and vote-counts can be our only interaction with them. When I argued that Jimmmmm had the wrong target value, and it was in fact correct, is a great example of that sort of situation. As players with limited information, it shouldn't be our job to make sure that the mod is correct in all things.
My personal opinion on this in games where backtracking is hard (such as mafia, or really any game with hidden info), is that once information is revealed, it is necessary to treat the gamestate as official even if it's wrong. For mafia this is a bit harder to track (except obviously, lynch flips), but I would say, after some reasonable length of time a vote-count is treated as official. Whatever that is defined as, it should at least include: "When an official vote count is posted, all previous vote counts are considered official game-states, and are treated as error-free regardless of the actual situation".
Ultimately it's going to be up to the mods, and whatever is deemed the "standard" rule can go into the standard rules, and if changed it should be noted. I'm happy whatever the standard is, this is infrequent enough as an actual game-changer. My preference is to give mods all power, because they're the only ones with all info. Players are free to correct mods when they perceive an error, but the safest bet is just to replace your vote/unvote. That should be sufficiently effective in 90% of cases. Mods should be extra careful when lynches are imminent.