I think the concern is more with what people in the immediate area (who may not have particularly been paying much attention) think. There is also the concern of escalating the situation beyond your control (fear that they might react violently).

Maybe the analogous situation is if you got mildly rear-ended, damaged cars but no injuries. Do you loudly call out the other driver and accuse them of negligence/recklessness, or do you calmly exchange information, file a police report, then let the situation be addressed when you are back home?

It's not really a good comparison, but I think it at least makes a little sense that you wouldn't try to call out the other driver on the side of the road after the accident (at least not without police present).

She specifically mentioned looking at this as a professional opportunity: beyond the immediate concern of possible retaliation by the attacker there's the concern for what other people might think. His friends might defend him and uninvolved people would remember her for the incident rather than as a professional and potential business partner.

Note that all of the property crimes you mentioned are different in one key way: a large subset of society doesn't initially try to blame the victim when it happen. Nobody is racing to explain that your car was asking for it or that you must not have taken enough steps to make your MP3 player unappealing, all of which are depressingly routine for victims of sexual assault.