While this isn t exactly the place to discuss theories and such there are actually a couple flaws in your argument The first one being that Totosai doesn t like Sesshomaru and therefore refuses to make any sword for him period The second flaw in your argument is that while Sesshomaru could have a sword made from one of his fangs it still wouldn t be as powerful as one made from the fangs of his father as he was much more powerful than Sesshomaru as a demon