I don't see what difference it would make. If you're going to impersonate Sifo-Dyas you might as well be anyone, using technology if necessary for the purpose of simulation. In the film the Jedi know that the file was erased by a Jedi. In the EU they believe this to be Dooku. But they do not assume that Dooku ordered the army or that Sifo-Dyas was necessarily dead when the army was ordered. In fact, in EU they find evidence that he was alive when the initial contact with Kamino was made. They specifically say during the film to not assume anything, and it goes directly against this line of dialogue to speculate that they do not practice what they preach and are actually fully committed to the conclusion that the army was ordered by an impostor and Sifo-Dyas was dead when the order was placed.