User blog comment:BenRG/Beacon Dorms - A Fanfic/Fanart Resource/@comment-17727644-20130909040323/@comment-4010415-20130909193732

"You will gather in the ballroom tonight; tomorrow, your initiation begins. Be ready. You are dismissed." - Glynda Goodwitch, episode 3, The Shining Beacon Pt 2.

So, no, they weren't in the dorms. They were in the ballroom. It makes sense. If they expect that at least some students will die during the initiation, why go through the trouble of getting all the students set up in the dorms only for some of the reserved rooms to end up with death-related vacancies?