Terry,
Did you ever consider that flooding the earth was done for more than one reason?
God forced the fallen angels to return to the Spirit Realm by flooding the Earth. The flood served as a dual purpose because it was also a judgment for those living on the planet. The angels that committed themselves to flesh and blood were connected to a virtual death with them unless they dissolved the human vessel and severed their chords. If God had chosen not to permit a searing of the chord when they dematerialized they would have been spent energy. Once the fallen angels had dissolved their fleshly containers and were back in the Spirit Realm, they were stripped of the power to materialize again in the fashion they had once possessed.