Seems to me the tribes are saying that having one Native ancestor over 100 years ago does not make you a Native. The people who end up in politics learn early to use anything for advantage. Warren used her ancestry to help her get into a good school. Bill Clinton missed the draft by being a Rhodes scholar. Mitt Romney got a draft deferment by being a Mormon missionary, and Donald Trump dodged it with bone spurs. And that's just a few of the more prominent examples--If we knew the whole truth, how many more of the Washington crowd would have elongated noses and flaming pants?
