I don't think it's KH3 for two reasons. First, because NP said themselves that they were just kidding. And second, because I don't think SE would allow NP to reveal such important information (unless they themselves reveal it at E3 OH EM GEE!).
3DS FC: 1306 6473 7511
Nintendod Network ID: xsorenx
Add me for Pokemon, New Leaf, and Fire Emblem, Mario Kart 8.