This will be our first stay at the Tree House Villas. Just when you think you have everything nailed down, you miss something. Thank you for your advice, I definitely overlooked that step. For anyone else who runs into a similar issue AFTER linking their DVC reservation in
MDE, make sure to book dining through the MDE site. I have several restraunt sites bookmarked. After linking our DVC reservation, used the bookmarks to open each individual site but those sites would only allow me to book one day. Returning to MDE and then making dining reservations allowed me to access to our entire stay.