In the context of AH.com Wars, this was the equivalent of Kamino. Its legendary vanished status is based on the fact that Thande himself has only heard vague legends about the real First Mosaic Earth from years ago (also abbreviated to FME).
FME, specifically the Republic of Yamania (originally created by GBW in real life) was the site of the cloning and pornwatching operations that produced the Porntroopers. The Kamino equivalency is helped in that Yamanian sounds fairly similar to Kaminoan.
FME also featured in the Series episode “The Dome Factor” written by GBW.