Some notes...
@RAT5
perhaps a pilot did have a look
BBC has what appears piece audio of the/a female pilot talking to ATC where she says someone "went out"... If the pilot had taken a look in the cabin at that time she would have known that the pax was held inside. She may have gone in later though.
About oxygen masks... Reports since the 1960s that the majority of pax dont read the safety cards. And in two well documented cases in each only 2 of 180 pax knew how to operate and put the mask on correctly. That is extremely serious. So hopefully the Darwin remarks wakens some people (dont get mad, please read the card). In documented cases, if they can get it working, people generally put the mask over their mouth only. Apart from pax negligence you have to wonder about the ergonomy of the design. Certainly something that experienced engineers should know about. So I am surprised that the design has not changed. Even a specific minor change could help.
Masks is not the only thing of course...same stories about taking carry on luggage, how to open doors, how to jump n slide, where are the lifevests and how do you put them on. One marine ferry case had multiple people putting on their vest the wrong way which caused the vests to put them head down, which drowned instead of saved a number of ferry passengers in a survivable situation.
NTSB said that part of the cowl was found 60-70 miles away. Wonder what the damage sequence will turn out to be. Fanblade, cowl, window.. Or cowl, fanblade, with window in parallel... The pax could have been hit by fragments or might have been injured by edges of the window construction. There is documentation of hits and fatal hits, but as far as i know not of such cuts/blunt.
On leading edge damage and risks... The Hawker HS door that struck and stuck to the horstab leading edge brought the plane down. During the investigations they found multiple cases where the door had opened, multiple cases in which the door was lost, but only that case led to an accident. I think it was a DC9 where maintenance forgot to refix the leading edge of the lefthand horstab. On the second flight after maintenance the plane lost the edge which caused LOC and crash. Both might be called freak accidents, but certainly inportant to obtain as much detailed data as possible. NTSB Docket system is the best, so we will get some information in the end.