It's really hard being a PNM. It's really hard being the mom of a PNM (veteran of 6 rushes here). It's awful being cut as a PNM but it's devastating watching your daughter being cut.
As an Auburn alum, I would advise your daughter to go all the way through pref parties and see what happens. If she doesn't end up with a bid, she should register immediately for COB. I corresponded with an Auburn mother last year whose daughter went unbid and then at the end of the semester, she received invitations from 3 or 4 sororities to come to informal parties. She ended up with a sorority she loved!