Rowan had to be careful with every information given by Enoch, and although he could trust the information that was given to him at the beginning, that time had long passed.
When Rowan summoned the power of his Final Form, he was extremely unsuitable to wield that power, and if he followed the vision showed to him by Enoch and his suspicion about the Primordial Record was correct, the Primordials were counting on his lack of knowledge and his character that was fiercely stubborn and foolhardy to push through the limits despite knowing the danger that such a thing would cause.
If Rowan had summoned the power of his Final Form without his absurd luck of following the fundamental rule of End, he would have long ago perished, and the Primordials would have been the winners.
