Some Warrell's clearly stayed in Convoy, I see a Thomas Warrill with son David in 1822 in Convoy, this is likely a typo or the original was difficult to read. (Also a son George, think he may have died)
If this is the David who killed Wilson, than his father Thomas and your James could be brothers or such.
Your biggest problem is the lack of records before c1820, there isn't even Tlthe Applotment records for Convoy.