Built in the age of pharaoh Nectanebo, founder of the XXX Dynasty, last of the authentic egyptian dynasties, the actual temple of Isis is not in it’s original place. When the massive Aswan Dam was built, the temple would have been submerged, so it was moved to it’s actual location with UNESCO’s sponsorship.
The geography of Agilkia Island was completely modified, to make it look exactly like Philae, where the temple complex was originally standing.