Are you skipping certain quest updates or scenes? Like talking to the prisoners or children? Any previous scenes regarding Astarion's "siblings"? There are two scenes. Or other camp dialogues you might have missed? I ask because I didn't rush anything and the graveyard scene played fine for me, as well as his follow-up dialogue. I just did it about 2 days ago. Are you talking to him after Cazador's death, encountering the Gur, then going to camp and resting? The scene should trigger that night. The only thing I had left to do was kill Orin, Gortash and go to the House of Hope. Only sidequests left were the clown and the Hag.
