Main characters have lost the final fight before in manga. Main characters have died. Sasuke has been in just as many chapters of the manga as Naruto has been, if not more. Title character means little in J-manga. Plenty of mains lose or even die. The movie also is not canonical despite what some reviewers are saying.
Naruto's clones disappeared when he went unconscious. Kurama is gathering the nature energy at this point, and he's already throwing it all into the attack. I do believe the fight will end next chapter, one way or the other. We'll get at *least* 1-2 chapters of epilogue. The fight may also end in a draw or be interrupted.
So far in this fight:
-Naruto's mostly been on the defensive, not being very serious
-He's tried to TnJ Sasuke, who isn't having it
-White TNJ land failed to move Sasuke as it always has
-Sasuke and Naruto have often alluded to "we'll both die"
I think the fight may have a pretty shocking ending, like Naruto actually dying or one or both of them going MIA. The movie is not canon, and most of the Naruto movies have not been canonical. Most OAV in J-manga are not related to the manga. Japanese manga is made for a Japanese audience, and Japan has a long tradition of film adaptations not being related to the manga.