Huh? She was dating Chris Brown not 50 Cent.
I dated and married a bad boy and you know what? He has never laid a hand on me. Of course, I have also told him that if he ever did he better get ready for a fight because he might be able to kick my behind, but I will go down swinging!!
She might have not been able to call because she was to busy trying to defend herself against his fists and apparently teeth. People complain all the time that others don't want to get invovled when they see something happening to someone else in public, so it was nice to see that someone did get invovled and called the police.
I think you are really making a leap here. Not sure how you are able to discern what her behavior is.

We would have no way of knowing what has happened in the past between them or what happened with this incident.
She was beat up by a guy, in the process of being beat up someone else called 911. She is cooperating with the police and their investigation. She sought medical care for her injuries, albiet not that eveining. I'm unclear how you can determine that "nothing in her behaviur says she is done"?