I'm also not sympathetic toward the instructor. The complaints about her being put on the spot ring hollow. If she is truly a professional and knows her material she could have handled herself. Put on the spot? Right.
Just FYI, it's exceedingly difficult to defuse a situation where a student hijacks a class or discussion group to talk about how Monsanto is more powerful than the American government.
Or when they hijack the class to argue that the US doesn't qualify as a democracy because there's no civilian control of the military.
Or when they hijack the class to argue that the US government is more socialist than any other in the world.
Or when they hijack a class to argue that a local political leader is as bad or worse than Hitler.
Or when they hijack a class on media portrayals of sexuality in youth to go on a rant about how their kids are good kids and they don't believe in exposing their children to offensive content and we live in a sin-cursed world.
Or when they hijack a class to argue that, in the context of how judiciaries can be outlets for groups to use constitutional claims to achieve equality, that equality is not a good thing.
It's extremely extremely difficult as a lecturer of any kind to be about to defuse situations where students are not interested in learning or facts but instead are passionately arguing low-information beliefs that they hold deeply personally and that they are not willing to suspend so they can take even a minute to think critically.
This combined with a serve-the-client mentality that has been fostered in most undergraduate contexts, which in turn leaves professors powerless to discipline or remove problem students, makes it very difficult to deal with these situations. It should also be noted that while lecturers are experts in the field they are teaching, many are not experts at teaching. University teaching requires passing a comp exam and then getting the gig. It does not require formal training in methods of education. So in many cases instructors don't have the skills or self-confidence needed to be able to deal with problem students even if they do have the knowledge to dispute their assessment of the issues.