If Pocahontas’s grandmother had Cherokee DNA, then that can also be tested with the DNA of all the descendants of that grandmother and all the descendants of that grandmothers siblings.
If this was Trump & not Warren, the MSM would have hunted down all the descendants and have bribed the $hit out of them for any prior DNA test of theirs or for then to take one immediately.
If Pocahontass grandmother had Cherokee DNA, then that can also be tested with the DNA of all the descendants of that grandmother and all the descendants of that grandmothers siblings.