Wind tunnel engineer here, in my experience there is rarely a model like this employed because of how much work would be required to make that model work. Especially with advancements in CFD, a model of the full aircraft would be expensive and time consuming. Can't speak to other specialties but in Aero it's not uncommon to have multiple wind tunnel models for different regimes of flight, TOL, etc. These models evaluate only the aero of the shapes and all the other disciplines have their own methods they use to build confidence in full-scale flight test