I don’t think just deaths are about whether a person deserved it - but if the death is justified. Jade was being used to do evil things and needed to be stopped, so her death, by whatever means or by how evil her killer was as well - was justified

That’s a way to see it, yeah. The very rules of the Just/Heroic conundrum are fuzzy, at best, given this is the only piece of information we really get about the issue.