I mean being captured by the Finn. Maybe her Price for her angreal/whatever-else was that she would return to them later, not of her own will. She obviously knew that she would be captured by them, as evidenced by her letter to Thom. While this could have been an answer she was given, I don't see why it has to be. Besides, it's a very Moraine thing to do, to request things in order to help the DR, knowing that the very granters of the wishes would demand in return her imprisonment. What surprised her may only have been how they used her.