If proper functionalism is true, then god is omni-ignorant

According to proper functionalism, a belief for an agent has warrant only if that belief was produced by properly functioning cognitive faculties. Accounts of knowledge are supposed to apply irrespective of the agent in question, even if that agent is God (or, if you prefer, a necessarily existent, uncreated, ideal cognizer). Unfortunately, this is where proper functionalism founders, i.e., proper functionalism is inconsistent with God having knowledge. Whether one understands ‘proper function’ non-naturalistically or naturalistically, accounts of proper function entail that God does not have knowledge. The upshot of this is that if proper functionalism is true, then we cannot apply our concept of knowledge to God; moreover, even if one holds that our terms or concepts apply analogically to God, any plausible way of understanding how our terms or concepts analogically apply to God leads to the same result—or to the falsity of proper functionalism. This result, however, is implausible, and gives us sufficient reason to reject proper functionalism as an account of knowledge.