Rumpole
Formerly known as "Hercule Poirot"
That looks to me like the bathroom/toilet. A door from dining into WC as I have shown it.Caylee is indeed in the living area (the same as great room). I will agree with your correction that it is the kitchen through the "arcetrave" (great word!) but only because of this picture:
If Caylee kept walking straight ahead she would exit the other door to WC that I have shown. I will go back and watch the Greta walk/interview.