Frans slap (P3V2)

I have a question. When Fran slapped and lectured that orphan from Hasse that was misbehaving and treating Rosemyne rudely, who was present? I thought they had to keep Rosemyne‘s (real) past a secret so why did he tell a full (from what I got) room of people about what she had to endure? Did I miss anything about the room being cleared beforehand or were only people there who already slightly knew about it?