You can have 5 in a room at the Deluxe resorts (with the exception of Wilderness Lodge). At AKL, only some of the rooms accommodate five. The regular rooms at the Polynesian, Grand Floridian, Contemporary, Yacht and Beach clubs and Boardwalk Inn (did I forget any?) feature two queen beds plus a daybed.
For moderates, Port Orleans has some rooms with trundle beds that accommodate five.