Abraham goes back to 1900 BC
Not conceding your timeline, but it is immaterial anyway. The question is, when were the Genesis creation stories written? Not before the Epic of Gilgamesh. Why not just dictate it to Moses directly? Why risk getting crucial details changed with oral tradition?
I'm not sure if Noah was still living in Abraham's time but his son Shem was.
As I said, if you are going to invoke miracles every time you turn around anything is possible. Newsflash to you. Individuals did not live to be hundreds of years old in the time of the pre-Hebrew culture. If there is anything real about dates given with all of the begats, it has to do with peoples, clans, tribes, etc., not individuals. Abel represents a clan of herdsmen who were wiped out by Cain, a clan of distantly related agriculturalists. Deal with it.