Hello there, Celestia! Welcome to planDisney, or should I say Bright Suns. We are so excited to hear you are arriving soon at Disneyland Resort.
Savi's Workshop - Handbuilt Lightsabers is such a neat experience that will be one for the memory books. This is one experience that requires you to pay by credit card at booking that will be charged if you fail to show. However, you should be able to use a Disney Gift Card (or other acceptable form of payment) to pay for the experience on the day of. Using more than one form of payment shouldn't be a problem.
If you have multiple Disney Gift Cards, I recommend registering them on the
Disney Gift Card website, so that you can actually just combine multiple cards all into one card. This makes things a lot easier than trying to store and remember balances on more than one card. Before our recent trip, we purchased a Disney Gift card eGift for a small amount and then transferred our other balances onto that one. We then added the Gift Card eGift to our Apple Wallets and it was so easy to use throughout the parks.
Celestia, thanks again for stopping by. We hope your visit to Batuu is prosperous!
Carrie