They cannot tell the girls recs are necessary to go through recruitment, because they aren't. Recruitment is a Panhellenic event. Panhel has an entity has no idea of each sorority's individual policies as far as whether a rec is required to issue a girl a bid. I know that sounds convoluted, but think of Panhel as mall management and the sororities as individual stores.
Titchou is right, nothing she can do about it now but stay positive and have fun!