Assuming that the Lissa info is from the book, I would like to know who Lissa is then I'd they failed the city.
It's hard to be more comfortable with ambiguous roles than I am, and I'm always complaining to trust instincts more than items/powers.... But at this point failing the city (in the actual results) and bring in the book are both pretty unambiguous proof of villain-hood. Is everyone who failed the city the people we need to kill? No. But I'd assume that the people we need to kill are in the subset of people who failed the city. Whether it's villagers and wolves in that subset, or wolves and "independents" (think Dexter WW), I think losing whomever is identified by that list is not a bad move at this stage.
Plus we have no real meat or suspicions to work with right now. So even in okay with using an item that we appear to understand enough (it's pretty straight forward. Obviously every street thug is not a cruminal mastermind, but it's still a criminal)