my bf M 23 was and I F 21, 15 months together, invited to a debut

So, my bf M 23 was and I F 21, 15 months together, were invited to an upcoming debut party. The celebrant is one of his closest friends' sister. I never liked this girl, we fought because of her so many times already. They would always hangout together 3 boys (my bf, the brother of the celebrant, and another close friend, and the friends' sister (the celebrant). They're friends for like a long time now, even before we met. I am already close to his friends, became friends with the girl as well, but I still can't trust her. And now, my bf and I were invited to her debut party my bf is being asked to be one of the 18 roses, I was told I was gonna be one to give 18 gifts. And I don't feel comfortable to let my bf dance with a girl I was jealous for, and the reason to some of our fights. And I want my bf to say no to being one of the 18 roses. Would it be fine if he declines the invitation? We would still go, but he could do 18 shots as well. Idk why the girl wants to make him of oh her 18 roses. She knew about the fact that we fought because of her before because I confronted her. I just feel like she shouldn't even ask my bf to be her one of her 18 roses in the first place.