A thought crossed my mind last night (It's probably too late for speculations because the beta is probably going to be released within a week but oh well...)
What if Amaria does lose her memory (which is highly likely since it happened to IRL Amaria), but also gets 'brainwashed' (or something along those lines) by Team Meteor? She might be forced (unintentionally) to flood her house, and we might have to battle her to stop her causing further damage. When we defeat her though, she may still be under control, so we won't receive her badge just yet. Then the story progresses and we will eventually face the leader for the current episode (I'm leaning towards Ciel or Adrienn - because the rest of the gym leaders seem to have their gyms at currently inaccessible areas. I'm still keen to believe that we'll be facing Titania in the Scrapyard).
In a future episode, where Amaria regains her memory, perhaps Titania could remind her that we defeated her in battle, since she probably would have witnessed our match - which is when we will receive the badge from her (maybe after another friendly battle).
...yeah, this theory is probably just too far-fetched, but one can speculate right? *hides behind an alleyway*