You most likely have tried the following, but I thought I would mention it anyway…
According to at least one family tree, Abner had several children. The tree indicated that most had middle initials. Were some of Abner’s children possibly named after his parents or his siblings? Have you tried looking for a Bennett family in 1870 with children (or parents) named Abner, Hershell, Virgil, Elnora, Rosie, etc.?
When researching for friends, I noticed that some of their southern ancestors moved around quite a bit and birthplaces (c1860s-1880s) were often incorrectly stated. I found this particularly true with Arkansas and Tennessee.