But now we get into the plausible reasons. James and Charlotte Robertson did, indeed, have Native Americans come to their house to discuss diplomatic concerns. I couldn't verify that those talks happened at the Treaty Oak, which used to stand at the corner of 61st and Louisiana, but I see no reason to doubt that when Native American delegations showed up to meet with Robertson, the shade of the big oak tree might have been a good spot. And he did meet with multiple nations (which, considering the deaths between them, is really extraordinary).