Board Thread:Manga/@comment-25933225-20190901125632/@comment-1327106-20190901153416

I don't think the prison in Shiganshina is big enough to hold all the Garrison members, and the wine was only served to officers. It's not like a rank and file person would have had the access (though Kitz and Rico would have had the rank).

Chances are most of the Garrison, and the Military Police for that matter, joined the Yeagerists, because the alternative wouldn't allow the current situation to happen. If only a portion of the Survey Corps rebelled and the Garrison and Military Police had united against them, chances are the Yeagerists would have been squashed pretty quickly. They only function because they have popular support and they've taken out the higher ranking officers who could have organized opposition.

As for Rico and Kitz, they were stationed in Trost and it's unlikely they would have had any reason to go to Shiganshina and be exposed to the wine. Chances are they're perfectly fine and just not playing a role in the current arc.