You can learn about manipulation techniques so you can spot some sooner… but ultimately it’s up to you to make a decision, and chances are you’ll either over-react, or under-react. It’s very hard to not make any mistakes, or spot the ones who spend their whole life learning how to manipulate others.
That’s going to be a “he said, she said” case. Chances are, since she was an activist in the US, that she might’ve been labeled as an “instigator” in whatever ID database they are using.