Why the HELL did Viren get to be in charge when Ezra abdicated?

Like, the man was in the dungeons for high treason. While possessed by Aaravos (which no one knew at the time) he openly attacked the entire castle guard.

I know that he was a serpent in Ezra’ ear to get him to abdicate, but why was he suddenly free and in charge, and everyone at the castle was just like “Yup, we aren’t questioning this”

And later, he says he’s going to empower their armies. So he uses the Sun staff to turn all the solders into zombies. Like actual mindless flaming zombies. And all the citizens see this happen. See their friends and family burned alive and become mindless bezerkers. And they cheer for this, they

I know it’s a cartoon. But how is everyone in Katolis except for our main trio such an oblivious wet sandwich? Viren is a cartoonishly evil madman, and he gets to do whatever he wants as soon as Ezra steps down.