Diana's advice is sound, but I'd concentrate on passing the exam rather than worrying about this.
Once you pass and pay the $50 to become an Associate, immediately submit an endorsement application for full membership.
https://www.isc2.org/Endorsement
If your application is accepted, you'll be asked to pay the remaining $75 of the $125 full member AMF.
Going this route might add 24 hours or so to your endorsement timeline, but is likely to be less stress than dealing with Pearson VUE's and ISC2's Customer Service teams!
