I assume you mean this pic?
If so, there are numerous pics and texts in ACIV that hint at A LOT of possible future ACs. Egypt is just a single one of them. I don't think the possibility is very high because that is pretty much the only mention of Egypt at all.
That's the one in the game. A picture was leaked of that character in Egypt and it was in game. This is the only one I can find. http://oyster.ignimgs.com/wordpress/write.ign.com/141181/2013/12/AC5.jpg