I think it's strange that different codes are given to different people. Oh well - use the one I posted and you should be good!
My invite was through an email. My promo code is FRIENDMACYS.
My Macy's is including Coach in the F&F Sale. I was there last night and ended up with a 35% discount because I got the 20% F&F discount and an extra 15% off for opening a Macy's account.