Perhaps; but as we have seen, there is very little demonstrable difference in his dimensions, which suggests to me that if the suit was at all loose, it would not be to such a degree that sculpting an entirely new suit (which would be a considerable undertaking) would be warranted.
I'm inclined to believe that guy is full of it, because he says they only used scale models for the first film. This is an outright lie, as anyone can tell you (and as you can see from simply watching the film, not to mention the special features, articles on the production and so on). Regardless of his obvious stupidity, I accept the possibility that a Tumbler was built without my having heard of it (can't catch every bit of news, obviously), though it seems unlikely.