I know a bit about Schoenstatt because my mother almost joined as a nun, and still stays in contact. They at least WERE very good - couldn’t really say about now although I think it is still attracting young people who want the genuine faith, but there was always a bit of a cloud of controversy around the movement, partly because they were sort of a break-away from the Pallotines, and partly because there’s been seen to be some borderline idolatry (to put it harshly) of their founder. My mum remembers feeling a little uncomfortable about this even in her most idealistic/ romantic days of being with them. All that said, every single one of the priests and nuns I’ve ever met from Schoenstatt have been very genuine and trustworthy, so your friend is probably better off with them than with many other movements. I still treasure some of the old letters and sermons and lessons etc from my mum’s convent days - they bear witness to a time when Catholics truly loved the depths and breadths of the Faith.
I’d be interested to know what your impressions are of them these days?
Editing the post, because I just wanted to add some info - it is very Marian in its spirituality, and was originally very idealistic about Education. The educational ideals had strong ties to the thinking of St Vincent Pallotti.
Is it still the case?