While its possible thats the case, I personally doubt it. How would Lamborghini know there are numerous paint issues? It's not like they hang out over at TFW or Siebertron so where would they find out it was a widespread issue? Maybe Lambo aren't happy with one of the repaints (like Tigertrack) that Takara had planned?
Dunno. And I doubt we ever will find out officially.
But VW own Lamborghini as well through Audi. And VW allowed the official use of an Audi in ROTF. As a decepticon no less. So I don't see the validity of that arguement.