Teams Breakout Rooms Settings - Presenters Missing in the "Manage Rooms" Setting

Hello! I'm hoping that someone can help identify a solution to a problem that has us dumbfounded. We have set up multiple Teams meetings where we need a handful of presenters to have the ability to manage the breakout room settings. We've found the setting to make this designation - "Assign presenters to manage rooms" - but unfortunately during testing, our presenters aren't showing to be able to select them. We either get a "We couldn't find any matches" or a "There are no assigned presenters to select from" error. And sometimes we're able to select one presenter, but no one else. We've tried adjusting the attendee settings so that everyone is a presenter, so that the specific people we need managing breakout rooms are set as presenters, etc. and we still have this issue. We can find no rhyme or reason as to why it works for some but not for others, and are looking for a consistent solution. Any help is appreciated!!! Happy to elaborate further as needed.