Now, Vader’s lightsaber being retrieved from the exploded DSII would definitely need a good explanation. Doesn’t it fall down the ractor shaft when Luke cuts off Vader’s hand?
It is about the same as Luke’s lightsabre falling into gas giant.
I always assumed it just hit the bottom of that big air vent, or whatever it was. Just because Luke almost got sucked outside doesn’t mean the saber did the same thing. The old EU even had a story where it was retrieved by an Ughnaught.
As for Vader’s saber, some of the early TFA drafts had the wreckage of the Death Star II being explored. There’s artwork of someone exploring Palpatine’s throne room under water (suggesting that s lot of wreckage hit Endor or the planet it was orbiting.). Johnson may have borrowed from these unused ideas.
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