One thing to keep in mind when researching Pamunkey ancestors is that there were only about 150 people on the reservation--most of them related to each other and already mixed with the free African American population before 1800. Most had African American names which came from the surrounding counties: Arnold, Bradby (Charles City), Collins, Custalow, Dungee (Brunswick County), Holmes, Holt, Miles (Charles City), Sweat (free in James City County by 1640), and Winn.

They had no choice but to seek partners off the reservation. Whether your name was Bradby, Brisby or Lewis, would not determine how much Indian ancestry you had.
Paul