Do I understand correctly that the pathways from the hatch above the bunks also goes through the galley? Or did I misunderstand?
Egress is always a concern for enclosed spaces like this. Airplanes actually evacuate fairly well - there have been enough examples to prove that.
My biggest concerns are so far this:
The alternate escape hatch possibly also necessitating going through the same area to exit (to be counted as a separate route, imo, it needs to go through an entirely different area. Just like your windows in your bedroom are considered an egress, and the door to your room is a separate one, both going different directions. But two opening windows are not necessarily two different egress paths).
The escape hatch being above a bunk. That is potentially very difficult in the best of circumstances, but with smoke present, when you are supposed to be staying as close to the floor as possible, needing to go into the smoke is a concern, both for visibility and smoke inhalation.
Configuration of it all in general, feasibility of escape in an emergency, how exactly the safety briefings are done, whether people can practice opening the hatch, etc.
By no means do I want to imply this operator was negligent or out of compliance. Those are just general concerns with the the situation as we know it. Terrible tragedy.