The Islamic prophet's foreknowledge of the Terfeziaceae's health benefits

[BrianSoddingBoru4]

Hilarious post hoc translation given that the term "species" wasn't coined until a millenium after this was written. I don't suppose that it mentions that the desert truffle isn't actually a truffle at all?

OFC translations are post-hoc. Modern English itself started 7 centuries after the prophet. Adding the word species explains the original saying in Arabic, but doesn't alter its meaning in any way.

The original saying simply says, "Truffle is from Al-Manna and its water is a cure for the eye". The term "disease" would be too an addition to clarfy the meaning. 

What he's tying to tell you is that the folk medicine existed before your prophet's scribblings. Your prophet didn't write down anything that hadn't already been know for centuries.

He has no source to prove that, the articles above backng up this affirmation are written by Muslim authors, clearly the folk medicine they allude to is post-Islam medicine;

Not exactly. From the article:

From early stages of civilization, desert macrofungi in forms of mushrooms and truffles have been used as food and medicine. Originally, these types of organisms were associated with Mediterranean region and were first recorded as poem in Egyptian temples as follows: “Without leaves, without buds, without flowers: yet they from fruit; as a food, as a tonic, as a medicine: the entire creation is precious.” 

'From the early stages of civilization' is pretty unambiguous, not to mention 'Egyptian temples'.

Boru