Just to clarify, are you ruling out that it's the cabinet purely based on her head being in a different position to the thing behind her, i.e. in comparison to the normal crime scene images?
Or
Are you implying that the thing behind her is not the cabinet, based on some other analysis of it?
From memory, I believe the bedside cabinets to have been the once popular Queen Anne style. These were usually pale cream in colour, with gold embossed patination. They stood atop bowed and curved legs, and were arched. It's practically impossible to say, with confidence, what it is, in the picture, she's almost laying against, but I'll hazard a guess that it isn't a Queen Anne styled bedside cabinet.