Splendor Solis is attributed to Salomon Trismosin, described in the alchemical literature as the teacher of Paracelsus. Nothing outside that literature attests him. Paracelsus, who names many of his sources and quarrels with most of them, never mentions such a teacher. The name itself reads as constructed, joining Solomon to a Hermetic epithet, which is a common pattern in alchemical pseudonymity.
What would resolve this An archival trace independent of the alchemical corpus, such as a matriculation record, a guild or civic register, a will, or a correspondence naming him, or conversely a manuscript study showing the attribution was added to an already circulating text at a datable point.
OpenEarly modern German archival history and the philology of the alchemical manuscript tradition.Owen Davies, Grimoires: A History of Magic Books