New Thought; It's not the information, it's the juxtaposition. Yes, genealogy is hard, but putting that next to questions of truthfulness is WP:OR not because any PART of this is untrue or undue, but because putting them together makes a conclusion that is not supportable. As a disclaimer at the top of a long section, maybe, but not as an answer to charges. Furthermore, let us look at the 3 (actually 1, 2a and 2b) that pertain to Cherokee.  

 1) many Cherokees refused to register when told to at the turn of the century. Yes, BUT those who refused were by and large full-blood Cherokee, did so in vehement protest of the idea of the Dawes Roll, were (or could be) added in the 1930s, and left the modern life for a more "authentic" lifestyle based on their roots. Definitely NOT the category Warren's 1/32 ancestor belongs to.  

 2a) Intermarriage; Cherokees had been intermarrying extensively since Georgia, over a hundred years before the Dawes Rolls, so "looks" were deceiving even then, meaning that ancestry and ethnicity were guarded jealously, but the "family" or Nation was exceedingly inclusive. Dawes Rolls were made very loose as to inclusion, and Warren's family clearly did not meet that loose criterion even then. Not a problem with Warren's genealogy. Which leads to 2b)  

 2b) False claims of Cherokee heritage. Since people in 1890 didn't have to "look" Cherokee, and if you claimed to be Cherokee at the time the government decided to give away Cherokee land, you got a huge handout to anyone who identified themselves as Cherokee, you pretty much had a boom of instant (not) Cherokees flooding the Oklahoma Territory. Sorting out genealogy when there were so many false claims made over decades (it took about 20 years), which may have passed into family lore makes the general question of Cherokee lineage more difficult.  

 Perfectly willing to accept that SHE has family lore and that SHE has believed it, also willing to posit that in spite of basically new evidence that her lore is wrong, it does not PROVE it to be without any basis, since genealogical research always has some questions. All of this is irrelevant, since the problem is not any small genealogical history, but a claim to be a Protected Class of American, which has a specific definition she does not meet.-