I'm fresh off a review of the Philebus material, and wanted to have another look at Plato the "Golden".
QuotePlato's school he called "the toadies of Dionysius," their master himself the "golden" Plato, [...]
Quoteτούς τε περὶ Πλάτωνα Διονυσοκόλακας καὶ αὐτὸν Πλάτωνα χρυσοῦν,
It seems that the word we're dealing with is χρυσοῦν. If that word is an adjective, and derives from χρύσεος, then it certainly does mean "golden". But if χρυσοῦν is a participle deriving from χρυσόω, then it may instead mean "gilded"--papered over with gold-leaf.
If my fanciful and doubtlessly flawed analysis has any weight, Epicurus may have been going for a pun here. Because "Plato" (Πλάτων) comes from the word platys (πλατύς), meaning variously broad, flat, level, etc.
If this was the intent of Epicurus' words, then Plato's goldenness was, as his own name suggests, just a false veneer, like the Platte River in Nebraska--a mile wide and an inch deep. All surface, and no substance.
Perhaps Don can come in here and bring me back to reality!