This is where I jump in and simply ask why YOU couldn't have tried to defuse the situation that you felt was being construed incorrectly by a passenger?
One of the things that I can't figure out is why we are all trained the same way and FA's can solve the problems on a narrowbody but call the purser on a widebody?
Why couldn't you have, as Eolson mentioned, told her that you were sorry that she was so upset and asked her if she would rather have a bag to place her stuff in? You could have told her that you were unaware of how the interchange happened between she and the other crewmember but newspapers all over the floor pose a safety problem because they make the floor slippery like banana peels. It is one thing if the area in front of her seat has the trash around it but when the papers, or other garbage, transgress into the aisle the problems arise. This is particularly significant because she is seated in front of the exit row and every impediment by the exit could cause loss of life in an emergency situation.
Why take it to the next level? You should have shut her down and appeased her feelings of ill treatment at the same time.
Amen Chris...
(although I am such a control freak, I always wanted to know when there was a problem. We had pursers on the 757s too and for a little while even had them on narrow body flights)