The islanders are homo sapien erectus, created by the Second Ancestor, Xor, with the assistance of the Eleventh, as an alternative to the Last.
They had similar development, but were not based upon the Cro Magnon template, rather continued the development of the original line from Homo Ergaster.
That stated, the DNA match would reveal the Second and Last as closest cousins.
The Second are a stone-age folk who have lived in isolation from the rest of the world, since coming to the island circa 30, 000 years BC, when all humanity was fleeing south due to the last ice age.
Captain Taris of an Ancestral Starship contacted them, and Empress Zhao Ræm took her people to the island for safety.
Taris lived many of their lifetimes, gave them an ethical code, and used his spacecraft's shields to protect and hide them, even from modern-day satellites.