Thank you for this posting. It points to some likely confusions of William Bennetts in the Georgia Bennett book.
I do know that Rachel White Bennett is my ancestor, because she is buried near her son William Benjamin and grandson Camelious Bennett, my g-g-grand-father, in the Fayetteville, GA City Cemetery. Some records list her maiden name as Jacob. Several records I had of Rachel's husband William Columbus, assuming him to the the son of William Columbus and Mary Frances Baugh, indeed don't make sense. Your William Columbus son of John fits known dates better. However, I do have some conflicts with your records.
I have no records of sons named Bartholomew or Jesse. I suppose one or both might have been sons of W.C. by his first wife, about whom I did not know. Twelve children of Rachel and W.C. are listed in his Will of 25 July 1822 in Jackson Co, GA. (transcribed into the Georgia Bennett book), but none are named Jesse and one is named Bartley, not Bartholomew. A letter written by Arnold Bennett, son of W.c. and Rachels' son Asa about 1917 (transcribed into the GA Bennett book) says his Uncle Bartley settled in Louisiana. He also says Asa and Bartley's brother, his Uncle William Benjamin (my ancestor), owned and visited land in Texas before settling in Fayette County, GA.
Do you have any ancestry of this W.C.'s father John? I have a John with brothers named William and Jesse, the three of them sons of a John Bennett who died in Isle of Wight County, VA on 4 October 1770. The dates seem about right, but I have nothing but names of this John's children, but got from the GA Bennett book that he descended from Thomas Bennett who came to Jamestown, VA from England before 1625.