I remember this was suggested before for JWE1, I'm going to guess by you.
Even though John Hammond referenced Disneyland, making it a canon part of the universe, if they aren't going to let us make anything close to Barney the dinosaur, I'd hazard a guess anything Disney-esque is probably off the table.
If we go to Europe in DLC I could definitely see Castles of some sort being a thing as scenery, but I'd think more likely along the lines of ruins (a castle wall fence might be interesting, but I'm not sure that Medieval theming makes much sense for a dinosaur park builder).