Hawaii started dine-in restrictions in September. Aulani's current policy as told to me by Aulani CMs on the phone, that you must be staying at Aulani to dine on property & either be fully vaccinated with proof of vaccination (card with ID, photo of card with ID, registered on the website that validates your vaccination status) OR negative covid test within 48 hours of your reservation for anyone over 12 years old, under 12 is exempt from requiring vaccination. We check in tomorrow & were told that everyone over 12 must go to the front desk to show their proof of vaccination or negative test (everyone in our group is vaccinated, so I won't have more info about covid testing, unfortunately) then receive a "dining" wristband that you wear during the length of your stay to allow you to eat on property. I've been told this is different from the "pool" wristband you get each day as a resort guest.
I was told by the CM on the phone that Makahiki needed to verify my resort stay before allowing me to make our character dining reservation, so I gave her my resort reservation number, she verified everyone in our party was registered guests of Aulani for the date we wanted, then she was able to give me my dining reservation number. I don't know if I could have done it online, but I would assume you would need to log in to the Aulani site with your Disney login, add your resort reservation number then dining reservations might become available? I called since I'm local & time difference isn't an issue for me.