I don't know for sure, but I suspect that as at most Catholic schools there probably are few or no nuns at this school. There are very few women entering convents today and the older ones are not being replaced. Most Catholic schools have only lay teachers who went through liberal indoctrination (the same as public school teachers) during their college years. The "teachers" at this school who made the decision to have the pro-abortion speaker belong to the Cafeteria Catholic group I define in post 14 above.
...and most of the nuns that are still around today are very liberal anyway.