I guess until the facts come out, we can dream up all kinds of scenarios.
You said — “Or just maybe, this was the girl that grabbed the would-be murderer by the arm and asked where was he going with those guns and that knapsack full of ammunition...”
No, not according to the article, if you read the details. They had an argument. An RA was “called” to mediate. He wasn’t there. He had to be called and he came there and he mediated. The guy left.
Later the guy came back (at 7:15 am). At that time he had a gun. And according to a witness who gave his account on the news, the shooter killed her first and then the RA came out of his room (probably because of all the commotion) and then then the RA was shot.
*That* was the sequence of events *as reported* by witnesses and from the news.
Regards,
Star Traveler