Dont read if u dont wanna spoile recodeds secret ending.

 

when yensid said "if the nobody and the heartless both disappear then the body will becum whole again" does that mean that braig, dilan etc. will return as well?

Well, this was something we knew since KH2FM, so it's not really a spoiler, but yes, assuming their Heartless have already been defeated.

i never played or even seen kh2fm so i didnt know

I remember in a Nomura interview that if someone's Heartless is defeated first, then their Nobody defeated 2nd, then they would in turn become a whole. Other than them merging together like Sora/Roxas and Kairi/Namine at the end of KH2.

One can assume it doesn't matter in what order they were defeated in, aslong as they're both defeated the original being will return. So yes, assuming their heartless is defeated Braig and Dilan shall return. One can assume they might even have memorys of their times as nobodys aswell when they return to their original selves.

Yes, once the nobody and the heartless are defeated, then the somebody comes back. We do not know if Sora defeated Braig's and Dilian's heartless because they might've been just a random shadow heartless like Sora's heartless.

so basicly if they becum whole again then lose their heart again then its over and over again

i never played or even seen kh2fm so i didnt know

 

Actually, it wasn't in the game, but an interview that was released with the limited edition version of it

I think that could be what Yen Sid meant by that Xehanort might not be alone

Yes, once the nobody and the heartless are defeated, then the somebody comes back. We do not know if Sora defeated Braig's and Dilian's heartless because they might've been just a random shadow heartless like Sora's heartless.

 

Except that Sora's Heartless wasn't just a random Shadow. It was because he has a very small amount of darkness in his heart. Braig though, obviously has something much much bigger and stronger.