I don't know if this always happens but I received a pin in the regular mail. Later I was playing around on the Disney website, building trips in my cart and looking at resorts. Then they started sending me emails with the same pin codes I got in the mail. It had the link to the pin website. I deleted the emails when I booked my trip or else I could share the link.
I just thought you might be able to try the same thing. Build a trip and save it in your cart. And maybe they will send you the pin email again?