From AD&D module C1: The Hidden Shrine of Tamoachan by Harold Johnson & Jeff R Leason, TSR, 1980/1981. “II Nedraw” is “Warden II” backwards, a reference to the colonizing spaceship “Warden” in Jim Ward’s Metamorphosis Alpha. This artifact is described almost exactly the same in the 5e version of Tamoachan in Tales from the Yawning Portal (2017), with the spelling clarified to “Ilnedraw”. The clear implication is that Warden’s sister ship visited Greyhawk’s world and influenced its history. Gary Gygax himself gave further evidence for this crossover by teleporting Jim Ward’s own D&D party through a portal in the Vault of the Drow onto Warden, and he was partially inspired by Warden when designing the crashed ship in the Barrier Peaks. Officially that buried ship is not Warden but it could be from the same 23rd century Terran culture, possibly even part of Warden II.