There was only one occasion bin Ladin actively denied responsibility for the 9/11 attacks, in the Daily Ummat interview. Note that this was a newspaper interview only, and was not carried out in person: the newspaper reportedly gave some questions to the Taliban, who came back later with some written answers. So given that the "inside job" theorists are so quick to assume the multiple other occasions when he or other al Qaeda implicitly or explicitly accepted responsibility, are fake, why is it that they automatically assume this is genuine? Is it not possible that someone within the Taliban issued fake answers in the hope to at least buy more time before they were attacked? Is it not also possible that bin Ladin was pressured to lie on their behalf, for the same reason? How about the idea that he took this tack initially because he didn't want to give America a pretext for war, and so hoped they would suffer more politically if they did attack Afghanistan?
Because the statements issued after that were not in any way clear "denials" of the attacks, at all, no matter how desperately the inside job theorists want you to believe that. For an example, see "news bbc co uk/1/low/world/south_asia/1585636 stm" (replace the spaces with dots) & ask yourself exactly how he's distancing himself from 9/11 here.