He's already been tried in Egypt (in absentia), and convicted and sentenced to death, so any return there would be, shall we say, brief?
the infowarrior
That's partly why I don't think Zawahiri has anything to do with Saudi amnesty. The amnesty deal is for Saudis.
I do recall some months ago, around the time of the Spring Wana campaign that there was some funny stuff going on between Yemen and Egypt regarding a brother of Zawahiri. I'd have to go back and look for the details.