I mean, based on the fact that no one died, that means x number of mafia members didn't vote to lynch and y members voted against someone that is already a mafia.
Now, two mafia members know each other. It's possible they voted for the same person, but spreading their votes out seems better. They are less likely to hit a only a mafia player that way, ensuring a night kill. I think it's more likely that they were both AFK than that they both voted for the same person. If they did vote for the same person, maybe they both voted for mafia and if a mafia leads the NK vote, no one dies (I would expect that any civilians that got votes would by lynched instead... Ginyu can you clarify on this point?).
I'd say it's likely that at least one of the other mafia members is AFK. I'd also say it's likely that at least one mafia member tried to kill a mafia member. From that point, just have to rely on your gut.
It just occurred to me that me being arrested may suggest to some that I am mafia and it took away my nightkill vote. If that were the case though, I wouldn't have only asked about someone using clairvoyance on me. The fact that no one has pointed this out yet makes me think it's not obvious, so if I were mafia it would be dumb of me to bring it up when I could hope that no one would notice. For that reason, I think it's best if I bring it up myself.