Aslan's ressurrection, or indeed any possibility that this might happen never occurred to Jadis. Although she knew the Deep Magic from the Dawn of Time, which she thought to manipulate to her advantage, she was totally unaware that there was a Deeper Magic from before the Dawn of Time, because she only arrived in Narnia, courtesy of Digory Kirke, at the Dawn of Time. Had she been able to look a little further back, she would have read a different incantation, that when an innocent being, who had committed no treason, was offered up in the place of a traitor, the Stone Table itself would be destroyed and death itself would be reversed. This lack of knowledge, combined with her own pride and arrogance, would ultimately cost Jadis her life.