It's not hard to properly identify an owl, and they typically hire really good people for that stuff. Source: my [relative] used to work for the forest service as an ornithologist.
Also: if they accidentally kill some non invasive birds by accident, that's still less destructive than letting the invasive species crowd out the original ecosystem.
Do you know what the forest service does? They are a conservationist organization within the US government. It's one of the most unambiguously positive parts of the government.
My relative would tag specimens of protected and endangered species of owls, note their locations, and then prevent loggers from destroying those habitats. [Relative] is a hippie environmentalist, and they literally would not have taken a job that harms animals.
Killing invasive species protects countless other species from extinction, so it has to be done. Those invasive species have their own habitat elsewhere, so they're not threatened, and they have to go.