The thing that everyone seems ignore is that there is a fire lane that is splitting the Nintendo construction site into two.
There is construction both North and South of the fire lane, but none on the fire lane. This leads me to believe that Hollywood version of Nintendo World will be split into two sub areas. It makes sense that the bigger plot North of the fire lane will house the Mario Kart ride and the Mushroom Kingdom. The smaller plot to the South of the fire lane would be for something else, most likely Donkey Kong.