I like torridon's idea of preference, as clearly they are (usually) determined. In fact, the idea of a non-determined preference seems impossible. AB seems to float around in a world where choices are neither determined nor random, without specifying what this means, except via the nebulous word 'free'. So he is in a hall of mirrors, or a vicious circle.
But this is presumably because he is starting with his desired conclusion - he wants to crowbar God into the equation, and he thinks he can do this via free will. We are free, because God wants us to be. But what is this freedom?