And so Velleius does not really reference, to my understanding, "a prolepsis of a god." Rather, he is saying that we have a proleptic faculty which disposes us to thoughts which leads to the idea of a god, just as we have a nose which functions in a way that gives us input into a final conception of a flower.
Hmm, I think I get where you’re coming from. A bee is not born knowing what a flower is and how to make honey, but they have the proleptic faculty to do these things without having to learn them from scratch through experience. Am I on the right track?