Bailey attributes VS10 to Metrodorus, corroborated with the fragments of Metrodorus...
The note seems to say: "Dueningius did not correctly infer from this passage that the book "Pros Menestraton" was written by Metrodorus, the sentence was drawn from a letter." And it must be the letter cited from Clement of Alexandria where the fragment includes addressing "Μενεστρατε Menestraton (vocative)" as the second word. It appears that Menestraton was a ruler of Miletus (3rd - 2nd century BC):
IONIA - MILETUS Bronze, (MB, Æ 20) v26_0080 Greek Coins
... Or not. I suppose there could be more than one Menestraton in the ancient world 
Metrodorus, though an Epicurean, spoke thus, divinely inspired: “Remember, O Menestratus, that, being a mortal endowed with a circumscribed life, thou hast in thy soul ascended, till thou hast seen endless time, and the infinity of things; and what is to be, and what has been;”
This reminds me of Lucretius's description of Epicurus traveling the universe in his mind.
Here is the Vatican manuscript excerpt...
https://digi.vatlib.it/view/MSS_Vat.gr.1950.pt.2/0255
402r
NOTE that Metrodorus's attributed saying does NOT have a red capital letter starting it. It just is inserted within the text. See musings about a "red letter" edition of Epicurean sayings (like the red letter Bible and Jesus's words in red).