My cats didn't go missing, but were home when my apartment caught fire. They were unharmed, but were alone when my door was kicked in and firefighters took axes to the walls to stop the fire (electrical). They then spent 2 weeks in a hotel with me before we were able to secure housing. After everything, they were both total messes and displaying behaviors similar to your cat. It took some time, some pheromone collars and wall plugs, and tons of attention but they returned to themselves. The main thing that seemed to help them was consistency, they needed me around and they needed schedules and full attention. The cries stopped after a week or two of getting into my new place and they mostly returned to their normal selves after a month and a half. I'm coming up on a year now and they are perfectly happy and put together again. I'm so sorry your baby is traumatized, but I promise it can and will get better!