They (B&K) always claimed that their end of the series was based on the notes by Frank Herbert that they found at some point. They however, have never disclosed

They (B&K) always claimed that their end of the series was based on the notes by Frank Herbert that they found at some point. They however, have never disclosed those notes, to at least give us an opportunity to verify those claims. I have a hard time accepting their revelation about Marty and Daniel. I also believe that their interpretation of the Butlerian Jihad deviates substantial from the idea of Frank Herbert. And that it is just the other way around, that they had to deviate from the notes by Frank Herbert (which it seems they only found after having written the prequels) to make them fit with those prequels.