So in other words, a group of people calling themselves a "tribe," which is not recognized by the federal government as a tribe, AND which accepted payment for "their" land 48 years ago, now wants to unilaterally renege on a contract they (or their ancestors) entered into, and attempt to accomplish by guilt trip that which they cannot accomplish by other legal means.
What kind of "stewardship" are they providing over the land that downtown Seattle sits on? Are they rotating the sidewalk crops? Are they maintaining the irrigation ditches?
Their appeal is significantly lacking in both specificity and logic.