as salam alykom
my humble input being an Egyptian who studied history of Egypt.
We were taught that Jacques Menou enbraced Islam and married an Egyptian, being of the Messenger's descendant or not was not confirmed in my history book.
As for Napleopn himself I did not study anything in this regard apart from him stepping into Azhar Masjed with his horses.
At the end I share Dan's Petitdija, Khairan and Senorita's opinion about who embraces Islam.
Islam is a gift it adds to the person who embraces it not the opposite.
Yet, according to Islamic history, the Messenger (sallah Allah a`alyhee wa sallam) said O Allah support Islam with the embracing of either two Omars (he was referring to Amr Ibn Al A`as and Omar Ibn Al Khattab). Alhamdulelah both did embrace Islam and were major assets as well.