Well, Weaver didn't kill Savannah when she was a real nuisance, or Ellison after his initial refusal to teach JH, so maybe she doesn't always kill at the slightest provocation.
I don't think it was a poor misdirection, in any case. I was unsure right away whether it was meant to be Weaver's plant (also because the internet transmission did mention the name of the plant or at least part of it), or not, unlike many others who seemed sure Weaver was killing her own workers. The episode right after, we saw the drone being recovered by someone not working for Weaver (or not any more at least, but it did increase my suspicion the plant wasn't Weaver's at all), and the one after that the guy Sarah shot turned up alive and he was taking orders from someone. I was pretty sure after that, that Weaver was not involved (other than to kill them).
I think the problem is that there is a great reluctance among parts of the audience to view/consider Weaver as anything but an evil terminator. She has killed a lot, but still, her actions as a whole remain ambiguous as to what her eventual goal is.