Mappy Monday- Watkin's Point Maryland as boundary

Augustin Herrman Map of the Chesapeake 1673

I have been doing some work on the  Carrow line that is in Carolina by 1663 and see similarities.
That family had the counties of Albemarle, Bath,Currituck,Beaufort ,Hyde and Craven form and reform around them between 1687 and 1748.John Carrow is in Currituck in 1735 Land Tax and in Hyde County in 1748. Did he move? Apparently not, the County of Hyde was formed in 1746 and he then is listed as property holder there.

Our original John Carrow who is brought into Virginia by Captain Samuel Matthews before 1643 must have started a family while on Mathews Plantation. John Carrow who is later Constable in Accomac County is deposed in 1663 as being 22 years of age. Did John Carrow II just move directly across the Chesapeake?

John the Constable is last found in Accomac in 1678. A John Carrow is living on Tackett's Lott Dorchester in 1730 in Thomas Tackett's will. That John and Henry and Andrew are found witnessing and testifying in and around Queen Anne MD and Kent Island until Henry 's death in 1762. Henry Carrow, whose widow, the former Mary Ringgold lives at Cox's Neck Kent Island is long described in records on Kent Island as living " where the road strikes out to the church near the wading place to William Ringgold's plantation".

What  I am wondering, actually, is do the boundaries between Virginia and Maryland via Scarborough's line at Watkin's Point provide the reason I do not find them in records? Does Accomac Virginia as well as the various Maryland county configurations camouflage them?  Carrows are found in Dames Quarter and Somerset County as well  as Dorchester and further north.