Random Yuuzhan Vong: Guys guys guys, let's go and just start rebuilding planets for no particular reason whatsoever! Just cause we're Yuuzhan Vong, you all know how generous and kind we are!
Other Yuuzhan Vong: Pretty sure we're hella evil, why would we do that?
Random Yuuzhan Vong: Because! How else will people write on these destroyed planet's most of which we have no connection to!?
Other Yuuzhan Vong: That is a fair point, alright but as soon as the Sith call we're going back to destroying planets.
Random Yuuzhan Vong: Deal!
And that's the story of how the planets were brought back. Head canon accepted, head canon accepted