Was the Sahara Desert actually created while Earth was orbiting the Sun’s twin star, or is the scientific evidence accurate dating it to between 9,000 and 5,000 B.C?

The latter is correct, that it was more recent and befell early members of the second human creation wave that came when the Earth had been repositioned in its current orbit and the divine human project restarted, and of course, followed the discovery of the human return by the Anunnaki, who then began manipulating humanity and along the way, in actual timing here more recently, created that devastating outcome for formation of the current Sahara Desert through inundating an area of human habitation and rich plant and animal life supporting their civilization.