Good news! You can use Disney gift cards for payment of your reservation and all around the resort at restaurants and shops, etc.
I'm happy to give you more advice but I would definitely advise reading through some of the great trip reports here. I would also recommend to look into DVC points rental. If you are not familiar with the process a quick google search should yield the ins-and-outs. It is VASTLY cheaper to rent DVC points than to pay Disney directly, even using discounted gift cards at a discounted time of travel. As an example, we went over Christmas this year. For kicks and giggles, I looked up the cost of renting DVC points or renting our Ocean View Studio directly from Disney. So the two nights renting DVC points would have come to a hefty $1,116.00 or $558 per night. Through Disney, the same stay in 2019 would run you $2,446.40 at rack rate including tax, or an incredible $1,223.20 per night. So you can save even more than 50% renting DVC points.
I would also really consider doing a split stay for your time there. Aulani is absolutely amazing and while you are there you may want to spend your time focusing on the resort and not running around the island. There are much less expensive places you can stay as a "home base" for exploring - and it is SO worth it to explore the rest of Oahu. The North Shore is beautiful and there are many great restaurants around the island, as well as worthwhile museums, zipline tours, Pearl Harbor historical site, and much more. I would aim for at least 4 nights at Aulani and then spend the rest of your vacation either exploring Oahu from another hotel as home base or hopping over to another island.
I was probably your daughter's current age when I went to Hawaii as a child - I loved it. Obviously this predates Aulani, but even without any Disney at all, it was so magical. What a wonderful thing for you to plan this special trip for her. Please let me know if you have any specific questions or if I can help!