William's Wiki page has different parents for him and a good bit of DNA test results.
Also, I had seen notes on Ancestry for some of this line being Monacan and buried in the many notes on the Wiki page is this note:
"William Evans marraige record was on the Original Rolls of the Monacan tribe in Amherst Co VA. There is a book named "Indian Island" which deals with this community.William Evans home estate was like an Indian compund on top of a mountains. He and his family and neighbors associated with the native Indian community there."
Even though the Wiki page has William's mother listed as Margaret (Gatewood) Evans, the notes go on state his parents were;
"He was the son of Thomas Evans and Monacan Indian Unknown.", which would explain why his own marriage would have been listed on the rolls as indicated.
Then there is this longer paragraph about their Native connections:
"CHEROKEE INDIANS In this county it is not generally known that we have had a settlement of Cherokee Indians for many years. A few, and a very few, of the oldest remain to tell the story and the younger portion who know it only as a tradition, are passing from observation by the mingling of races, one of the results of the great upheaval produced by the war. In that portion of the foothills of the Blue Ridge mountains in Amherst County, known as the Tobacco Row mountain, Bear mountain, Stinnett’s and Paul’ s mountains, from five to eight miles south of the courthouse, a race of people exists today claiming to be Cherokee Indians, and not without satisfactory proof. The older part were typical Indians, of a rich copper color, high cheek bones, long, strait black hair, tall and erect [of?] form, stolid and not emotional like the African, but of as manly bearing as come of Buffalo Bill’s best specimens. The original settlers came to the county at an early period. William Evans, a Cherokee Indian first resided, about the time of the Revolutionary war, on Buffalo river, in Amherst County. His daughter Mollie Evans married one, William Johns, son of Mallory Johns, an Indian, sometimes called a Portuguese, who lived to an advance age, said to be 114 years, and died at the house of his grandson William B. Johns, in the “Indian Settlement,” as it was called, and by which it was known when I first knew them. There exists a tradition to this day, amongst these Indians that Mallory Johns, William Evans, and John Redcross, all came from the south, and it may be that they belonged to the Cherokee of North Carolina, who found their way here in the visits of the Indians then made on foot along the air line from North Carolina, to Washington to see the Great Father as they do now on the railroad, and that either in going or returning they stopped by the way and took up their abode here. Beyond the tradition I know nothing reliable, but my theory as to why they were here is doubtless the correct explanation."
The only consistency on Wiki is that his father's name was Thomas Evans.
It seems that the Native connection is well-established and that the parentage here on Geni needs further research / documentation since it's different than what is on Wiki.