If she stays dead. Also AO would only make a new goddess of magic anyway, if he bothers at all.
Also this whole kill her then make a new goddess of magic is old. Either keep the Goddess or ditch magic. Killing her, bring her back, kill her again, bring her back, kill her again, blah blah blah. If you are going to bother to kill a major aspect of a campaign setting... KEEP IT DEAD or don't bother.