He doesn't cut her any slack. Mostly suggests that the clarity of analysis that she encouraged, led him to understand the reasonableness of Christian truth. She wouldn't be pleased, but as the author put it, God can even use a talking donkey, why not Rand.
I’m guessing he missed her words on original sin and why living in a universe controlled by some unknowable, untouchable deity that can change the rules and turn reality on its head would make life unlivable.
He’s also probably missed how prioritizing abstractions (eg, society, god, etc) that don’t actually exist over things that do exist (like individuals) leads to the individual becoming expendable.