Allen did not know anything about the danger and his teacher also did not tell him anything even though she already knew about the danger.
Currently, Fiona became too busy to know about the details of the person who was targeting the orphanage and had a connection with Michael. First of all, she also knows that if she reveals that news to Allen then you will become very worried about his family and there could be a chance he does something reckless.
Because of this, before going to the normal world she wanted to gather as much information as she could. Before anything she needed to know what is the relation between that person and Michael who is currently present in the prison of the Guardian association.
The Commander of the guardian association already tried to talk to Michael after getting to know about this information but unfortunately, Michael or his big brother did not want to reveal any kind of information.