It is so complex and very hard for both girls: one has his baby, the other is his fiance. But neither of the girls should choose him.
The man is definetely dangerous... and not trustable. Even if your friend get married with him because of the baby( or maybe she still have feeling for him) , they will devoice someday in the future if the man beat her. In canada, it is against law. If you want to stay with this kind of man, you need to be strong and brave enough for your future.
See if the girl is strong enough to be a single mother, if not, it is clear what's to do then.
It is alway easy to say and hard to... Hope ur friend will be fine.