Tallifer
Hero
Yes, several online and physical dictionaries, as well as several years of French lessons.
In the original French, you'd stress the second syllable (making it "meh-LAY"). But in English accentuating either is acceptable. However, "mee-lee" is not, imho, acceptable. The first syllable varies from "meh" to "may" in English, but is never "mee".
And changing the pronunciation as jargon specifically for RPG use... that seems more than a little... silly and hubristic.
Get off your high horse. Do you pronounce Paris like a Frenchman or like the rest of the English speaking world?