I don't see any solution for the hell these people have created for themselves
option 1: cancel Lindsay Ellis for saying horrible horrible things adjacent to a now-forgotten children's movie, lose her unique voice and perspective, someone who had a wide reach and at one point was a strong proponent of your cause (and did plenty of cancelling on her own), and prompt the bad actors to move on to scrutinize the next target to cancel
option 2: circle the wagons and protect Lindsay Ellis, proclaim the people harassing her are all bad faith actors, proving publicly that you'll look the other way as long as the sinful person is someone you like enough, otherwise known as the B-Dubs Hypocrisy Special, which leads to the person being quietly shadowcancelled anyway by everyone embarrassed by this behavior