The thing with the Discovery Center is that it's already not fully a one-to-one recreation of the Visitor's Center from JURASSIC PARK, which fits in with the land technically being on a different island. As such, that gives Universal leeway to pick and choose whatever details from either the PARK or WORLD movies they deem appropriate. So I don't see any conflict with leaving the exterior of the DC alone even if the land as a whole is rethemed to JW.
They would hardly be the first exposed-to-the-elements animatronics in Orlando, and I suspect ways could be devised to keep figures sheltered to some extent when they're not "performing."
Setting aside money considerations (which I'm sure is a factor to some extent), it seems like such a no-brainer. Even with the new coaster, I have to believe there would still be plenty of room for several experiences comparable to that Spinosaurus one.