I think people need to remember why expansions are built. To draw more people. I don’t think they would expand Nintendo before opening. Why waste your (theoretically) sure fire attendance boost and a large portion of your expansion area before the park opens.
Any subsequent Nintendo additions than what we see in the art will almost certainly come after this park opens
That makes sense, but what if they delayed Classic Monsters to open the Nintendo expansion first? It's a win-win either way.