According to the article she had done that but who knows for sure her protections might have been inadequate in some way.
This is what I was talking about:
Did you know that you can create a totally, top secret group on Facebook that only you, and people you invite to join, can see?
http://mashable.com/2013/05/26/how-to-secret-facebook-group/
See also the “Secret” column here:
https://www.facebook.com/help/220336891328465/