You certainly did place a big gap between Genesis 4 and Genesis 5. YOu claimed that the people menbtioned at the start of Genesis 5 were completely different people form those at the end of Genesis 4, living millions of years later. Despite the fact that there is absolutely no reason to suppose that they aren't the same people.
You've got to put that gap - now billions of years - somewhere in the narrative or abandon your whole interpretation. So where do you put it now ? In Genesis 4 ? Between Genesis 3 and Genesis 4 ? In Genesis 3 ?