It’s been confirmed that the various islands will jump around timelines, so I’d be surprised if Nublar wasn’t either:
a) us running the original 1993 park/creating the original park
b) us rebuilding it in the aftermath of the original movie
Personally I think a) is a lot more probable based on how the interviews I watched went. If nothing else it’ll probably be an opportunity to be Hammond ourselves and create that original dinosaur park with all the buildings originally included.
I might try and dig up that interview again... just watching his face and how it lit up it’s pretty obvious that Nublar is something special, I really doubt it’ll disappoint.
Don’t disregard b) just yet, perhaps Frontier have created a scenario on Isla Nublar based on the cancelled Jurassic Park animated series, where players will rebuild and successfully open Jurassic Park to the world.
https://jurassicoutpost.com/entire-first-season-cancelled-jurassic-park-television-series-revealed-exclusive/