Regarding the seating plan as depicted in post #1496 by Etud lAvia and accompanying comment;
In a previously posted image of a group of three seats, which was a still taken from a Russian video of the crash site, it appeared that only the seat to the furthest left (if facing forward) of the group was affected by multiple small holes in the seat back.
Were this to be the group DEF in row 37, to the rear of the cabin and just forward of the lavatories &c, it would only be this seat, marked in yellow (D37) whose back section would be directly exposed to the area aft of the seats, as the other two in the group have seats behind them (row 38).
Might this be relevant, considering the similar appearing damage to the R4 door top panel?
http://avia.pro/sites/default/files/...rbus_a3211.jpg
NB Regarding Kulverstukas' remark that this is a Ural airlines plan - it was from the article first linked to in your post, but that isn't your fault if the website has used the wrong image - does anyone have a seating plan for the airliner in question? Thank you.