No, you are not refunded for the tickets in your package. The GAD voucher entitles you to a one-day ticket, or if you have a multi-day ticket (like in your package), you can redeem the voucher for fastpass cards or the Mickey ears figurine with pins or you can donate it.
You can't apply the value of the GAD voucher to an existing ticket or package. If you want to use the GAD voucher and upgrade it to a 6-day ticket, you can either:
book a room only reservation with no tickets (and no dining plan)
or
book a package with one day tickets, save the one day tickets from the package (they do not expire), and use the GAD vouchers (which expire December 15) to enter the park, then upgrade the GAD ticket to a six day ticket. This doesn't actually save you money, but it does mean you have one day tickets for everyone in your group for your next trip. The one day tickets from your package can be upgraded on your next trip to the number of days you need. Your financial outlay would be the same as booking the package with tickets, but you would have a head start toward your next trip's tickets.