My first guess would be secundas study (she might be in the vdsm room), second have you been to stratum 3 it might be a requirement, second have you done stratum 4 sequence 1 the magician (could be a requirement due to reasons), is blanche still in the cafe? You may have to score high enough on the mini game for her to be let go (speculation), failing that check all maps for blue and red exclamation marks. If that fails I don't know you may have found a bug.