After posting my question, I googled and found conflicting information (Surry Co or Rowan Co?) about the source of Saponi Indian intermarriage.
From a wikitree page [https://www.wikitree.com/wiki/Austin-3026 Joseph Champness Austin ]
INDIAN ANCESTRY:" John, Jr identified himself as a Saponi at a court hearing in Surry County. Valentine was also identified as an Indian at a court hearing in Surry County. Later, it was discovered the Richard (son) and Joseph were identified by the state of Virginia as Melungeons (Not of pure European blood). Since four of the five known children have been identified as "mixed blood" it is felt that there was only one mother for all the known children."
And then from a blog page [ https://johnclinard.wordpress.com/early-austin-families-of-va-md-connections/ ]
John Austin, Jr. tells a North Carolina Court he is a Saponi Indian, 1755.
(Abstracts of the minutes of the Court of Pleas and Quarter Session, Rowan County North Carolina, 1753-1762, 11:72, 19 April 1755)
Whereas John Auston a Saponia Indian and Mary a Susquhanna Indian and Thomas a Cataba applied for a pass to the Cataba Nation being now on their journey to conclude a general peace with ye Catabas in behalf of the the said Nation and also presented 3 belts of wampum to said Court by which the said Treaty is to be concluded.
Will need to do more research to confirm these sources and investigate whether they are even concerning the same family.