Create your account for MDE. As you are DVC members you may find that account works. From MDE you can see your link your package and tickets - assuming you have the correct confirmation number, the TA loads it and of course the big one, that Disney's IT is actually working LOL!!!
Then from MDE you can make your ADRs, reserve your FP+ events and generally plan, book and schedule every minute of your holiday in the happiest place in the world