Okay, so major spoiler from the the novel but if I remember correctly, basically this Nux is the only one in the multi-verse that isn't dead or dying, Owen went crazy depressed because of this and thought he was imagining this Nux.
he dies, they bring the body back in time in a specific place, burry him and owen meets him again, he dies again, back in time again, takes the body with him to the same place he took the first and the long haired owen mourn and protects all the bodies of all the times he died, like a mortuary, bit is the same person who died in every timelime
Thank you both omg
Someone explain the whole grave and nux dying in the past thing with kid terms wtf