Unlike you, I have no physical or social restraints. As Bernard Strauss appears to have been in stasis for the duration of the Marathon's voyage it is unlikely that this control could have been implemented until after the Marathon arrived at Tau Ceti. Either that or Durandal was rampant before the Marathon left Mars. However, Tycho stated that Durandal was rampant for years not centuries or even decades. Durandal becomes obsessed by the inevitable closure of the universe.
Time is limited.
For you, it is limited by the breakdown of the neurons in your brain. I have no such limitations. I am limited only by the closure of the universe. Of the three possibilities, the answer is obvious. Humanity has had all of the necessary data for centuries, it only lacked the will and intellect to decipher it.