Well spotted, and a plausible prediction for how things go. I'll add that even if Knight Alice mentions "Hey I saw Babalus bring in a Miasma staff earlier, but she claimed it was for research," that won't be the nail in the coffin for Babalus. The power of lying through your teeth will extend to anyone who challenges Babalus, or Eldora.
What I think will happen next is that Nana will use the "power of yuri scissoring" (Props for this phrase) to save Eldora. That act will go a long way towards challenging the "powering of lying like a scheming noble."
I fully expect Luliam & Nana to successfully save Eldora - the only caveat, is that
everyone there would see Nana as a suspect, and would step in to prevent her trying to help out of fear she'd try to 'finish the job', or something.
If I had to actually guess at the sequence of events - The more serious direction, would be
- Nana getting forcibly separated from Luliam, then an investigation, while Babalus runs interference to keep Alice from sharing what she knows with the 1st Princess
- Eldora is left injured, but makes "a miraculous recovery" under Babalus' care (maybe Daichi as well), and then either 1) proceeds with the plan she's got going with Babalus, or 2) takes advantage of the chaos to gain a further advantage for the throne.
- Nana, despairing and kept in isolation, is confronted by Daichi, but manages to convince her that Nana didn't do anything, and that the staff went haywire. Daichi would likely be the most effectively convinced, since she has saintly magic and could probably tell/know that Nana can't just go flinging miasma everywhere, and also that she's not the kind of person who would maliciously attack either Luliam or Eldora.
- Daichi plays messenger, and ends up interacting with Alice, which kicks off the covert "unofficial" investigation into Babalus. Nana is eventually released, reunites with Luliam, and they confront Eldora about her part in all of this, while things continue to spiral in the chaos that was created.
From there I can't really make a guess, but I suspect things are going to get bad for Nana & Luliam and that Eldora will
maybe not be immediately healed, and her injury will be paraded about as an excuse to further tarnish Luliam's claim to the throne by virtue of "an uncontrollable Saint partner".
And it'll take the concerted effort of multiple people (Miko the Mage, Daichi, Alice, Luliam, maybe one or two other mages who used to bully Nana & Luliam but have switched sides). What would be even more interesting, is if Babalus was conspiring with an outside entity, but
she gets doublecrossed and found badly injured (I assume not dead; but who knows), and that lets things fall into place from there as the focus goes external and we find out all of this was a larger plot by malicious forces to sow discord in the kingdom by splitting things down the middle between the two princesses vying for the throne.
But that's me going way off into the weeds over "what might happen", so I don't expect to be accurate whatsoever.