In my opinion, the model would not be an unauthorized copy given that it's primary purpose was for some other task and the inclusion of the work was merely inci

In my opinion, the model would not be an unauthorized copy given that it's primary purpose was for some other task and the inclusion of the work was merely incidental. The unauthorized copy arises when someone gets the work out of the model. Of course if you make a model explicitly for the purpose of evading copyright then the courts will see through that ploy.