Lmao. Oh this is going to so terrible and fun. She gets to destroy her own perfect life by shooting two teenagers who she actually likes. >.>;

I don't think she'd go for the kill shot unless she has to. She knows she could take him down without one, and unless they've got the ramifications known in the aftermath of the Iron Eye mission, she wouldn't risk it unless she absolutely had to.

But she could be watching the confrontation maybe, not actively taking part but seeing it's not working and piece together her own solution. If Billy's the caster of the reality, it makes sense that it would unravel if he weren't holding it together. And if his magic made her first shot deflect or not as effective as she'd intended, a second one isn't that hard to get off either.