Does the creation reveal God?
I don't believe humans can uncover the will of God by unaided reason and/or by reflecting on the creation. I don't believe the will of God is written in our DNA (though I don't know how much environment affects the genes of a developing human or the infant child). I think God revealed foundational moral and relational truths to us from the beginning and that he added to those through prophets, priests and leaders. I think too that he enables us to use those foundational truths and additional materials in daily living and experience so that we can develop other moral truths from them. (The biblical Wisdom literature—Proverbs, for example—shows that God teaches generations through prior generations.) I believe that God has acted in self-disclosure in history through pivotal events and people and covenants he established.
I believe David knew the heavens declare the glory of God because he was taught it that rather than by deducing it by unaided reason or having it built into him as part of his humanity. And the God whose glory he spoke of was not some Aristotelian conclusion—it was the God of Israel so we shouldn't generalise Psalm 19. When he said the heaven proclaim the glory of God he wasn't thinking of some God or other or a God—he was praising the one true God who revealed himself to Israel. David knew the heavens proclaimed God's glory because he already knew the God the heavens proclaimed and that God told him (and his fathers) that he had made the heavens.
I don't believe Romans 1:18-32 is talking about truths deduced by unaided reason; he's talking about truth God had revealed; truth that the creation supported and exhibited. And as it was with David so it was with Paul. The God Paul spoke of in Romans 1 was not some generalised deity, some "prime mover" or "ultimate cause". Former atheist Anthony Flew might talk that way but he and Paul are lights years apart. The God whose creative power is shown in the creation is the God who had revealed himself to the human family. This we can be sure of, no one came up with all the moral truths of Romans 1:18-32 by making rational deductions without special revelation.
So creation does proclaim God but we only know that because God said, "I made all this!"