Received Confirmation/Invoice

Received confirmation/invoice in the snail mail from WDW Travel Company. Actually, received couple. The first one is for WL. The second one is for GF (after we upgraded from WL to GF) showing the two payments we have made already. Since we paid off the balance couple days ago, I expect to receive another one shortly. Both documents show the infamous ZFZ code and nowhere does it say that a PIN number is required. But, since the CM from CRO stated WDW will honor the discount code as long as I do not make any more changes to the ressie, I will trust their words on it.