There are no 'what ifs'. Naruto sealed all of Kyuubi's chakra into himself, enabling him to defeat Madara. However, Madara sends Naruto to a different dimension as a final action of revenge. "Only Dragonslayers can kill dragons? Ignorance. Only Godslayers can kill gods? Arrogance. Heh, I'm Uzumaki Naruto!" Earthland had better prepare, because an unpredictable maelstrom has arisen.