Zecharia Sitchin did make predictive claims in his work, specifically about the return of the Anunnaki. He claimed that the Anunnaki would return to Earth in 2003 to reclaim their gold. However, this prediction has not come to pass, and Sitchin has been criticized for making such claims without evidence.
The Mythical World of Zecharia Sitchin: Exploring Ancient Astronauts through English Quiz