There is quite a bit of supposition here. For example, Eve was tempted by satan and ate from the tree. She in turn gave the fruit to Adam which ate from it. The fall consists of all of these events. In Gen. 3 God talked and pronounced judgement on each individual culprit but all steaming from the same series of events.
BTW- Can you link to a detailed genealogy that dates to 20,000 years ago?
The accounts of creation depicted in Gen. 1 and 2 are not poetic but historical narrative. Hebrew poetry characteristic is not rhyme or meter but parallelism. These come in three forms, synonymous, antithetical, and synthetic or constructive. Can you point to any of these in the creation accounts?
Then why did the bible say this.
"In the day that God created man, in the likeness of God made he him; Male and female created he them; and blessed them, and called their name Adam, in the day when they were created."
Notice the verse states God created both Male and Female, but referred to them both as Adam, not Adam and Eve. The bible here itself proves that Adam is a general term "mankind" in the creation story here, not a proper noun.
The parallel is clear God created male and female together as the verse states both male and female were made, but only used Adam, this denotes he made mankind together. If two actual people were made named Adam and Eve, why does the verse reference both male and female to Adam only? Again, the world "adam" here is used as a general term, not a proper noun.
If you believe in history, science, genealogy and archeology we know over 100 different tribes populated the earth as far back as 75,000 years ago. This far exceeds the genealogy of Adam and Eve as actual people.
Andamanese and Bantu are two of the oldest.
To me it's evidence that God created male and female at the same time and called them mankind 1000's of years before the Hebrew fall story. Did he make them, did we evolve from some form,,,another long debate. Myself, why man may have been primitive and obvious has genetically evolved, I believe he was always man, not evolved from a monkey.
Many tribes picked general terms as names. Again, I have no doubt that eventually two Hebrew people existed named Adam and Eve, but mankind long existed before this. The bible makes a clear distinction using Adam as a general term for mankind and Adam as a proper noun, but we choose to use Adam only as a proper noun, a person, not a general term. That's incorrectly dividing the word when it's obvious Adam was used both ways.
When we do so we can connect scientific evidence with the bible smoothly and not look foolish when we claim man has only existed about 6000 years. That flies in the face of all the proven sciences.
Since we know "adam" in Hebrew means mankind and Eve means life. It may be possible that God created two types of species with male and female gentics and referred to it only as adam "mankind" When the word Eve "life" was later used, maybe that denotes man evolved into a greater human form.
Also, Gens was written about 1500 BC, by that time other creation stories existed. Many suggest Moses even used themes from previous creation stories, just worked it to fit Hebrew history. Read the creation story of the Miao that existed before Moses, could it be Moses copied some previous themes.
I certainly respect your views and find it an interesting subject.