Name Four People in the Garden

"Ἐπιμελείσθωσαν δὲ καὶ Ἀμυνόμαχος καὶ Τιμοκράτης τοῦ υἱοῦ τοῦ Μητροδώρου, Ἐπικούρου καὶ τοῦ υἱοῦ τοῦ Πολυαίνου, φιλοσοφούντων αὐτῶν καὶ συζώντων μεθ᾽ Ἑρμάρχου.

And [you all] let Amynomachus and Timocrates take care of the son of Metrodorus, Epicurus, and [of] the son of Polyaenus, so long as they study and live with Hermarchus.

I see what you mean. The way "Ἐπικούρου" is placed in the middle does seems to suggest your interpretation. I suppose the singular appositive could apply to both. Still, I think we would expect Polyaenus' son, even if named Epicurus, to be named as a separate appositive on Polyaenus' side of the καὶ. Although, with names, maybe that would have seemed redundant.

Thank you for pointing this out!

This is great!

What is the source for the info on Polýainos' son?