Wing body fairing separation
We have had to replace a Qantas wing to body fairing on one occasion after it was damaged by a catering truck coming down from 2left. They are a custom fit to each airframe no two are extactly alike. The question is whether the fairing left of its own accord or was it pushed? The oxygen bottle loss would probably take place in either event. My guess is the fairing separated aerodynamically and what is shown is secondary damage including the loss of the bottle. As the fairing separated damage to the fuselage at that altitiude was inevitably caused by the differential cabin pressure likely to be 8-6.5psi at crusie alt and the volume of cabin air taking cargo and the bottle out what probably started as a smallest hole enlarging it to what is seen in the photograph. No eveidence of heat
is apparent. The fairing may have been loose or damaged and gone unnoticed.