This is definitely the family; it has so many Jameses it's difficult to sort them out. The James Jr. who went to Roane County, TN, had at least two siblings---probably more--Matthew and William, who married sisters and migrated to Logan County in western KY. I'm apparently descended from one or the other couple. I am not sure that James Jr. ever made the move to western KY, but a son of his was definitely there for a short time before moving back east about 1811 where his parents, James and Mary, and his siblings had settled in Roane County.
James Jr's, Matthew's, and William's father was, of course, James, and, from a deed, I believe their mother was named Mary. Another researcher and I have found quite a bit to suggest that James Sr was part of the Cecil County, MD, bunch and came to Anson County, NC, from there. It's probable that claims that he was the son of Moses are correct. Of all the Jameses running about the Carolina frontier in the mid 1700s, this one appears to me most likely to fit as the son James mentioned in Moses's will.
The recently deceased descendant of James Jr through son Thomas, who went to IN, was named Jarvis Alexander. I don't know who inherited his genealogical data.