Is there any publicly released footage of the incident? I only read about it in the news and if the reaction is justified imo depends on what he exactly did to her.
Taking part in such an event (sadly) often leads to a certain loss of privacy which one should be aware of. On the other hand pointing the camera on him even after him indicating he doesn't want to requires a certain amount of ignorance.
But then again, I cannot really judge the situation and need to leave that to the investigators.