I was running a poll there, with the already known result (the fact that the execution, which broke the defense, had taken place).
His vote was the last one for Revan. Usually, when they don't want to be obviously exposed, they often spread their votes, but let's say statistically, they add a large number of votes to their own. Especially since there was a defense. And that's why those who started the movement are the least suspicious, but those who finished it are more so. And there was a good vote from Yashur, and a neutral vote from 2 people.
By the way, even if he hadn't added his vote, they probably wouldn't have immediately accused him; he often acts strangely here.