From your description, I'm not sure if we agree on what a mesh is: a mesh it's just the database that controls the ground elevation, it's doesn't have anything to do with the texture representation.
Since KDFW is a fairly flat area, it would be difficult to see much differences with an addon mesh so, if you are sayig that around the airport is all default scenery, could be you are refering to the photorealistic addon scenery that is missing, and not really the mesh ?
In any case, I don't see why an addon photoreal scenery wouldn't work together with KDFW, as long as you keep KDFW on Top of it in the Scenery Library, which is the general rule that is valid for every airport, that airports should always be on top of large photoreal sceneries.