In US Native/Indigenous usually call themselves either by their tribe or "Indian." White people are the ones that generally use native/indigenous more even though natives call themselves Indian more.

Since the context was US civil rights you can see how I came to the conclusion, since it didn't make any sense someone could simply declare their heritage is from an extra-continental nationality and thus I was wrong.

In any case in the context of US civil rights, the Indians (native) are a far more reasonable conclusion than Indian (Asian) so at best it is a shared failure of communication.