The study I watched of Genesis 6 made it pretty clear, to me.
Genesis 6 is not clear. It certainly does not provide sufficient information to reach the conclusions you and the author of that study postulate.
Genesis 6 appears to suggest that God is mortal, and perfectly capable of interbreeding with humans. It said, "The sons of God looked upon the daughters of man...". It did not say, "The fallen ones looked upon...".
I just don't see how you are authorized to interpret the "sons of God" as loosly as you choose. That goes the same for all of the other Scripture you choose to very loosly interpret.