Dame Zabine (and she is a dame worthy of the title) is a fucking LEADER. She can motivate and she can get people in line in moments. She's good at dealing with raw recruits and her superiors alike. They don't make women like that, they just happen. Losing out on an officer like that is unacceptable, so Polidoro better get to work on training her properly. Sure, she's going to need a lot of training to smooth out her numerous edges, but she's worth it.
Polidoro seems, frankly, kind of bad at communicating with and connecting to his subordinates beyond pure strategy and tactics. Officers like Zabine can fill in that gap. You will always need to delegate, especially in armies. Hopefully, he realizes this at some point.