Wait one goddamn second... Parró should know this isn't why we came after her. We only went after Iowa because her dumbass storm wizard had the bright idea of scrying our city. Otherwise we wouldn't have cleaned them up until much later. Did she not know what her scryer was doing, not know we were in Mitakihara or is she testing us?
She's playing dumb because admitting that we came after their asses in response to them scoping out our city would be unwise. If we didn't already know they'd done that for whatever reason, admitting to the scrying would be incriminating them.
There are ways we might not know, such as if Constellation had poor internal communication so the one who figured out the scrying didn't explain the details and instead just pointed Sabrina at the problem like a weapon. Another way we might not know is if the timing was coincidental, and we had not actually been successful in backtracing their scrying. This would plant a seed of doubt that maybe there was another group responsible for the scrying we detected.
Parro does not know what we do and do not know, and part of what she's doing is trying to tease that out.
By this point, she will have figured out that she and her crew are not going to win by force of arms. They've had time to think about exactly how that fight went and how many of the little flourishes were done purely because we could and not because they were strictly necessary. And they've had time to test the walls and bars of the cell they're being kept in.
So, the next most logical means of escape will be the social engineering angle. Sabrina was an obvious enough choice to try and speak to from the perspective of an outsider. Grief benders have a nasty reputation, which would indicate Sabrina might be less strongly attached to the alliance. Sabrina's different racial features and english fluency is also likely to contribute to the idea that Sabrina might be easier to peel away than any of the other members of the alliance, especially given Iowa's origin within the anglosphere. If Sabrina wasn't in the loop for whatever reason, Parro could take advantage and try to play us against the others.
Iowa targeted Mitakihara in the first place in order to acquire Sabrina's services one way or the other, be it by directly shanghaing her, by threatening civilians to ensure our cooperation, or by swooping in to play hero rescuing us from an abusive situation where the people around us are just using us. She is likely leaning in to that original plan to see if she can still make it work.
That isn't to say they've underestimated us exactly. They may well realize trying something like that is a long shot, but given they have no other real option, slim chances are better than no chances.
Of course, this is all just wild speculation on my part. We'll know more as the conversation progresses.