Call DVC Member Services (RCI should give you the phone number in its confirmation notice). Give them your RCI confirmation number, and they'll give you the reservation number that's in the Disney system. They'll also ask you for Guest names and allow you to give them your flight info for DME and set up the Dining Plan, if you want either.
From there you should be able to use the Disney reservation number to link to My Disney Experience, etc.
We stayed in a 1-bedroom at Beach Club a couple years ago using my parents' banked week from their Cape Cod timeshare that they weren't going to be able to use before it expired.
-Rob