The Great Star Gazer actually has seen her death but she does not know the entirety of it. She has seen that the start of her death is when the God of Mischief Loki appears in her sanctum. This is the point in time that even she cannot change as it is a fixed point. She cannot even speak about her death because it is a taboo topic that will engulf everything around her in chaotic causality.
Even the Great Star Gazer knew why she was given the most powerful artifact by the Norn or what they are famously called as the Fates. She is the most powerful seer of this generation and has led the northern kingdom to safety all these years. She did not despair of her death because she knew that her fate is like a transaction.
