Boy!This stuff is hard to sort out. That's for certain.
Yes, the Wilburns were allied with the Wallens/Wallings many times...And also lived in Hawkins/Claiborne/Hancock Co TN...And they were also allied with the Seal family in Claiborne Co TN too.
Which is why the given name Wilburn appears in so many families with roots in eastern TN...like your ancestors.
And yes, my ancestors (Wilburns were in eastern TN) having lived in Wilkes Co NC before that time frame. My Wilburn ancestors were in Wilkes NC in 1800.
But other Wilburns living in eastern TN, were from Giles, VA..So not ALL Wilburns who lived in eastern TN came from Wilkes NC...
Stephen Wilburn (b. 1766 VA) m to Mourning Walling Wilburn lived in Giles, VA before relocating to TN...
Stephen Wilburn and Lewis Wilburn were brothers and both sons of Richard Wilburn...BUT they were NOT the only two Wilburns of their generation who left descendants in eastern TN..There was also a James Wilburn who appears on land records in Hawkins Co TN in 1808.Both Lewis and Stephen named a son James...so I suspect that James was another brother who died before 1838.
If I can narrow anything down for you, I will let you know..