That would seem straightforward, but the problem is that no one else discusses this text’s appearance in al-Hakam; indeed, several scholars have argued that the Surid myth did not appear until after his time. (The Arabic text of the surviving work of Al-Hakam is here, though I cannot read it.) Michael Cook, for example, said in 1983 that the story first appears in the Akhbar al-zaman, though obviously from an earlier source. That text can be no later than 1140, and no earlier than 904. He says al-Hakam makes no mention of Surid—but based on indirect citations from later authors like al-Maqrizi. However, it is unclear how many scholars have used al-Hakam’s text; one article I read, for example, took all of its citations from al-Maqrizi’s Al-Khitat, written around 1400. It’s true that al-Maqrizi does not attribute the Surid story to al-Hakam, but then again al-Hakam wasn’t citing it in his own name, according to Greaves, but to “chronologers.” This problem is complicated by the fact that there is so very little academic work ever done on the Surid myth, an al-Hakam’s text has never been published in full in translation. The extant English translations are all partial, and the most complete translation of the section on Egypt focuses only on the history of the conquest, making it unclear whether the translator omitted some or all of the folklore included therein.
But if we knock out the account attributed to al-Hakam (and ask what, exactly, Greaves was citing), we still have the issue that Murtada ibn al-‘Afif asserts that he read the account of Surid in the works of Abu Ma‘shar, written around 840 CE, almost exactly at the same time as al-Hakam. Was he wrong, too?
It’s enough to make a person want to give up.
There is one interesting thing I read in trying to research this: Martyn Smith, a professor of religious studies at Lawrence University, suggested in a 2007 article that Surid’s name is not a corruption of the Greek name “Suphis” from Manetho but rather is a play on words reversing the consonants of the prophet Idris’s name, Idris being the same and Hermes and Enoch, who perform the same function as Surid in their respective stories. Thus D-R-S becomes S-R-D. This strikes me as the kind of thing that Islamic writers would have gotten in trouble for, and it doesn’t accord well with the evidence that the Islamic names of the pharaohs were derived from a corrupt Syriac version of Manetho’s king list.
So my plan is to contact some of the experts in medieval Arabic literature and see if there is one of them who might be willing to tell me who actually said what.