One example: The introduction of his new narrative began with Dolores dying in Teddy's arms. How did Ford know William would stab Dolores?
Not exactly....but he's well aware of humanity's propensity for violence. He doesn't know what is going to happen...only that something will.
Ford told Bernard..
"You needed time. Time to understand your enemy. To become stronger than them. And I'm afraid that in order to escape this place you will need to suffer more."
Ford kept the hosts in the park because he believed they needed more time to truly come to understand the nature of their reality. And he wanted them to have 35 years worth of suffering at the hands of humans before he set them free. Ford knew that if the hosts had built up a store of memories — memories of being tormented for human's entertainment — that their final ascension to consciousness would be more devastating and complete.
He waited 35 years for the hosts to gain sentience, we're just seeing the culmination of his plan