Hi Jean!
Yeay! Your trip is almost here!
For any dining within a park, you will need separate park admission. In the case of Akershus Royal Banquet Hall, each person will need park admission to Epcot.
An option for dining with Cinderella, the Fairy Godmother, Prince Charming and other members of her family outside of the parks is
Cinderella's Happily Ever After Dinner at 1900 Park Fare in the Grand Floridian. Since this meal is located at a resort, no park admission is needed. Cinderella's step mother and sisters lend a fun twist to this dining experience.
Another, slightly different option, is the
My Disney Girl's Perfectly Princess Tea Party also at the Grand Floridian. In this experience, girls can enjoy a pampering tea experience where Princess Aurora makes appearances.
Hope this helps! Have fun with your princesses!