I think your Levi may have been the grandson of my Charles. What are his dates? I branch off through Jane.
Re Ann Marshall, I do not believe her father cd have been Alexander, as he is well attested and was evidently not married to Mary Branch. There seem to be other Marshalls in the area, but my knowledge of Pittsylvania/Halifax is pretty much restricted to what I have been able to gather on-line.
Do you know anyone actively researching this line? Wish I cd help you more, but I think we're in the same boat.