She was a woman in engineering in the 1950s and 1960s, which meant that the default structure of the field assumed she was exceptional and peripheral rather than typical and central.

She was a Native American woman, which added another layer of assumption about who belonged in the field and who did not.

She was not exceptional in some general inspirational sense.

She was exceptional in a specific technical sense: she was one of the mathematicians who could do the hardest problems in a field that had some of the hardest problems in American engineering.

That specific, technical form of exceptional is what the record, read carefully, actually documents.