I would make explicit that her beliefs about her subjective probabilities are inaccurate observations of her implied underlying logically omniscient, consistent belief system. She can then assign each possible underlying consistent belief system a probability, and update that assignment once she realizes that some of the possible systems were not consistent. What this comes out to is that whether she should update her belief in God or Objective Morality comes down to which of her beliefs she is less certain about.
I would make explicit that her beliefs about her subjective probabilities are inaccurate observations of her implied underlying logically omniscient, consistent belief system. She can then assign each possible underlying consistent belief system a probability, and update that assignment once she realizes that some of the possible systems were not consistent. What this comes out to is that whether she should update her belief in God or Objective Morality comes down to which of her beliefs she is less certain about.