Don't feel too bad! If there'd been any significant possibility of Pilar doing that, Cayden Cailean would've made different plans in the first place!
So it's not really that Pilar could've changed things that much by hypothetically being a different sort of person, even if it would've changed things if she'd suddenly acted differently without any gods being able to predict that.
Cayden Cailean only steered events this way in the first place because it was a very reliable fact that Pilar was too much of a subby sub to want to do anything without orders, even when that would've obviously benefited Asmodeus.