I have an update finally. YSL called me back yesterday and they apologized left and right for sending me worn shoes and promised me a new pair. I have to send them back and when they recieve mine, they will ship a brandy new pair to me :) The lady also asssured me that they will double check the new shoes to make sure not to send me used ones again!
I'll let you know how it all goes! Thanks again for all of your support!