Taking into account that field extraction has only a 20% survival rate, Olivia in turn has only a 30% chance of healing these poor people, with the caveat that it would take a tremendous amount of concentration and energy to heal the neurological damage!

The downside: they remember nothing of who they were. They'll still have basic skills, like feeding themselves, speaking, etc, but their personality as it was before is sadly gone due to Taraxa influence. They'll have to develop themselves from the ground up again--but it's certainly a more hopeful outcome than the alternative.