The issue comes down to the various Christian camps in regards to the days of Creation, and how they relate to the modern scientific method.
There are generally two major schools of thought:
1) Young-Earth Creationists which reject any and all notions that the Earth is >10,000 years old, and reject any attempt to make the timeline longer, including carbon dating and other methods that state dinosaurs existed well before humans.
2) Old-Earth Creationists and Theistic Evolutionists. People that are in this camp believe that the days of creation were not literal days, but relative to the viewpoint of God, and therefore agrees with modern scientific method. In the case of their belief, they would state that your reasoning of the Genesis account is wrong, and that the days are more inline with what science says in some form or fashion.
For cavemen, you have 2 arguments. The YEC crowd would believe they weren't humanoids at all, or died off prior to the flood. Old-Earthers and theistic evolutionists may hold to differing beliefs, that they did exist when science believes they did, and with theistic evolutionists, they were who science believes they were.
So how would such a view play into the Adam/Eve narrative? Adam and Eve would be the first humans with a soul - the first homosapiens, after whatever created them was finished (such as evolution).
Hopefully that helps explain the differing viewpoints. I don't think VGC is really the right place for this kind of discussion, because most people aren't going to give you the various Christian viewpoints..
Back from the dead, I'm afraid.
