Disney lately is about acquiring IP outright, not licensing - that whole Avatar thing in Animal Kingdom is the outlier, and was a deal made before buying Marvel and Star Wars.
Licensing Nintendo IP for theme parks isn't something I think they would be interested in and I don't think Nintendo had any plans to be bought by Disney.
Universal makes more sense because most of their stuff is built on licensed IP.
Oh, and that picture of KidZone above? Looks like whatever Nintendoland becomes, it should cover around half that space. Start with ET and work up from there, according to a poster with a good track record on a WDW fan site.