No. You do get zero interest for 6 months,IRRC. The discounts are sometimes offered to card holders in advance of the general public, and there are sometimes a different inventory for Disney Visa card holders when discounts are offered but I have never seen a deposit made with a Visa card fro early access to ongoing discounts.
If a DV discount is available, all you need to secure that offer is to put the deposit down with the card.