Couple of comments.
I'm thinking if there ever is going to be RCI availability there, it would be early in the life of the resort.
The reason I say that is that DVC had quite a scandal with the State of Hawaii and was forced to stop Aulani sales for several months. Seems they understated their MF's just a teeny bit (33%). So they had to guarantee those who had already purchased that they'd have subsidized dues for the life of their contract, and refile all their docs before the State of Hawaii would let them resume sales.
Jim Lewis, the President of DVC, lost his job over that fiasco, and he wasn't alone.
Because of the total suspension of sales for several months, the resort is open but I don't think they've sold many points there. So if there is going to be avaiability, you'd think it would be before the sales pick up and owners are booking heavily.
The other comment is that, if I were going to do an RCI exchange to Hawaii, I sure don't think it would be to Aulani.
I doubt if I'd go to Oahu anyway -- it's my least favorite island. If I did, I'd just go to the Wyndham. Aulani is located sort of at the armpit of Oahu. I'm sure the resort, and the surrounding resorts, are lovely...but it's really off the beaten track in a fairly low-income part of the island.