I didn't get from the whole issue that Helena isn't friends with Babs or that she's a crazy killer. It's that Man-bat appears to be on a rampage and she feels like he should be put down-and thinks he would agree with his humans side. She seems to be wrong about him, actually. But while she doesn't want a lecture from Babs or Dick it seems more like it's more about her being in a situation where she thinks a Bat monster is trying to kill her and so she's particularly annoyed at the idea that her priority here should be protecting his well-being. She's not an outsider who's really disapproved of, she just knows they'd disapprove of her blowing this guy's head off even though he's rampaging.
Iirc, it starts out with her shooting wide. So it's not that she's saying, "I'm an outsider! Nobody approves of me!" so much as we're seeing her when this monster's attacking her and she's saying, "Yeah, guys, can't tell you how much I love that no kill policy. I'll feel great if this guy winds up mauling a dozen people because I didn't take him out."