Why couldn't HxG just debut Emily, Lexie and Samara as they are?

I watched episode 1 and 2 of Prelude and though there are girls I'm rooting for (Jayla and Aoi), I feel like it would be weird seeing them with already familiar faces. I wonder why couldn't they debut the 3 as a trio or add someone else from DA? I read Ezrela denied HxG's offer (I don't know how legitimate that info is) but couldn't they have gotten UA? Or Marquise and Mei? There are 2 rumored finalists right now (if leaked info or pure speculation, I'm not sure but there was an accidental reveal of one of the finalists in the show itself by an editing mishap) and honestly I don't see any of them adding anything new or exciting. If anything, they feel like they have the less impact among the members, like a filler member. I don't know. I'm just not liking the direction for Prelude especially if rumors are true.