Egypt is a corrupt country. The military isn't very religious, atleast not the top brass, similar to Pakistan's. They climb up the ranks via nepotism and corruption, and receive guidance from their "education" in USA/UK.That would make Sisi a Jew if that rumour is to be found true. I wonder how Sisi managed to climb up the military and political ranks if he's been rumoured to have a Jewish mother in a country that's very anti-Jewish that rose after the creation of the Israel state in 1947.
The rumors are that his Jewish mother's brother was in the Haganah (precursor of IDF).