The location of the damage is right where two of the Oxygen cylinders are approximately STA 800-840 ref IPC 35-20-00 and was wondering whether the passengers actually had a supply of oxygen as all the bottles are linked in parallel so when the bottle left the aircraft the system would quickly bleed away. Obviously in the intial part of the incident there was sufficient Oxygen in the system to open all the PSU doors in the cabin, this may explain why some of the passengers were feeling sick as nausea is a symptom of altitude sickness.