GAZBERT thank you for your close up pic it has given me more detail and am able to offer another theory on what might have happened and possibly the cause.
That fairing is notorious for being damaged by catering trucks, as it is adjacent to the galley door 2 right. Supposing the fairing was holed on its last transit and went undetected or a pre-existing hole re-opened. If the hole eroded in the air flow and opened up to a size that eventually blew the fairing off ( crew report of a door problem prior to event) then as the remnants of the fairing support structure twisted and turned in the airflow, a weakening of the pressurized skin eventually gave way causing the decompression.
I think an oxygen bottle may have fallen away but not because of its own failure, and the material coming out of the hole might only be the side wall lining and insulation blankets( heavy canvas covers)
Just another theory.