The proposed relationship of William Garvin Greene as the father of HG and WGG is supported by DNA evidence indicating shared ancestry within the family lines.
Specifically, DNA evidence confirms a great aunt / uncle relationship between BG (a descendant of the HG ancestral line) and GG (a descendant of the WGG ancestral line) with 1213.99 cM of shared DNA across 29 HIR segments.
This match is consistent with their placement within these shared ancestral branches.