I noticed the same thing -- in my mind, this kid was about 4 feet tall, slight build, and hanging with big guys, but I was wrong. And Tessa, apparently taking a short cut from one side of the park to the other, to get to her dorm -- but it was dark or getting dark and she was by herself, and she probably wasn't dawdling around -- she just wanted to get back to her room and study, etc., but she never made it.
Those young guys were looking for someone just like her to walk by that night -- someone to rob -- but -- they also had at least one weapon -- just the right thing, a quiet weapon.
I would think, from what the article said, the pathway she took was something that students knew about and used -- just what she was doing that evening.
I did the same thing when I was in college, but it was here in NC. I walked, often by myself, took shortcuts when I could, all over a fairly big campus, which stretched over about 10 city blocks near downtown. The student body was about 12,000 undergrads in dorms or private apartments, and several thousand grad students who lived off-campus or in married grad student housing. It was surrounded by a very fine neighborhood and other areas offering rental housing/apartments and older housing or apts that offered cheap to inexpensive housing for students. A mix somewhat similar to where she was, I gather, but it was not in NYC, and it wasn't near a neighborhood mix of Harlem and nice, refurbished housing.
I never was afraid, and there were no incidents in the four years I was there -- but that was several decades ago.
Bless her little heart. Smart enough to get admitted to Barnard. And in wonderful New York -- one of the most amazing places in the world. Everything is there. She, with her own ideas of what she wanted to study and to do in her life, excited, bright-eyed, and raring to go. Now just simply gone.