You're right, it shouldn't happen, but I don't doubt that occasionally it does. It's certainly unfortunate but I can see how, with these huge recruitments, one of those phone calls could be missed. It must have left an awful taste in her mouth for sororities.
That's really awful!! You might want to let the Greek Life Advisor know.
Something similar happened when I rushed. The PNMs were suppose to meet at 11am. So around 10:50 I started walking from my dorm to our meeting place. When I was approaching the meeting place (it was around 10:55), I got "the call." By that time it was too late, I had already met up with some friends. I ended up watching from the window at the Union.