The Costco Citibank card has a photo of the owner on the back of the card for added security. If the card was rejected the first time the merchant should have looked to see if the purchaser was the same as the photo. Hopefully the stores have time stamped video cameras where they can pull a picture of the purchaser. Did you file a police report? That may help convince Citi that you did not make the purchases.
Likes: mmb and Neil Maley