Thing is, it's almost gotta be about something other than what it looks like. I mean, Minerva never intended to kill Diana in this fight. She described it to Psycho as a distraction, something to hold her off. There's little point in capturing Etta if Diana's dead and can't freak out about it. But if she doesn't kill Diana, she gets captured. Those are the only two possible outcomes, really, and Minerva has to know this by now. And of course she's certainly not acting very distressed to be caught here. Also, I read that panel where she's like "because I want to play with my food," and my immediate, instinctive, visceral response is, "she's lying through her teeth."
I have no idea, though, how much of any of that is intended by the text and how much is just loose plotting or my own perception of Minerva as a character.