The answer(s)
2020-02-05: No, they weren't.

The story
The Yaghan, also called Yagán, Yahgan, Yámana, Yamana or Tequenica, are one of the indigenous peoples of the Southern Cone, who are regarded as the southernmost peoples in the world. Their traditional territory includes the islands south of Isla Grande de Tierra del Fuego, extending their presence into Cape Horn. They have been there for more than 10,000 years.