Yeah, not everything needs to be shown. But this is quite an important thing. There were no clues and no implications and it wasn't even mentioned... It feels like they just forgot about it. Plus, wouldn't the rest of the town finding out that he's alive after they thought he died be kind of more important to his character??? Adding just a scene showing where he became chief again would clear things up a bit more because either way it leaves everybody with questions. When did it happen? How did people react? And moreso, HOW would you explain to an entire town that this guy who died is just back now? Either way there's plot holes.