I wonder if the Latinization of Gunthamund as "GVNTHAMVNDI" was influenced by the Latin word mvndi (world). You see that kind of stuff somewhat regularly. For example, Hierosolyma as a Hellenization of Yerushalayim (Jerusalem), influenced by Greek hieros (sacred), Secunderabad as an Anglicization of Sikandarabad, influenced by Latin secundus, etc...

