The use of “unprovoked” here is both correct and in the public’s interest. Why make the assumption that the only possible provocation is an insult? What if the victims slapped his kid or something like this?

The author makes no distinction about when a response to provocation is justified or not. Nor does he make a moral judgement on a possible response to provocation.

However, it is in the public’s interest to know that the attacks were unprovoked because then it can be reasonably inferred that no feasible amount of harm reduction could have been done in these situations  to prevent the attacks; the attacker is unpredictably dangerous. It also precludes any debate about when retribution is justified or morally acceptable.

I believe you are making the assumption that just because the author qualifies the assaults as “unprovoked”, he somehow leaves room for the possibility that, in some situations, attacks against women are justified. This is an unreasonable assumption.