How Original a Work is the Tractatus Logico-Philosophicus?

I published in Philosophy a play re-creating Wittgenstein's viva. Although the play is based on the historical 1929 viva, in this recreation, Wittgenstein receives a proper grilling from his examiners, Bertrand Russell and G.E.Moore, and they end up failing him for insufficient defence of the main theses of the work and for lack of originality. The play came in for some foolish and dishonest criticism by Michael Cohen and, in this paper, I respond to that but, more importantly, illustrate the originality of Wittgenstein's later work by contrasting that with the Tractatus, much of which was derivative.