So I’m thinking Ezra is there to save Kallus. Since the whole gist of this episode is the rebels planning a way to save the imperial spy (aka Kallus), then one of them is going to have to go in there and get him. Can’t be Zeb—sadly—can’t be Hera, can’t be Kanan either. Puberty hit Ezra like a train, so he at least looks different, and has a smaller chance of getting recognized by the others. He’ll just be another rebel, and they can use that to their advantage.
So I think that’s what this all is. I could be wrong, and I won’t be watching the episode anyway either, so who knows. Just a speculation.