As I remember the first AAIB report was said to have stated that the Captain after his initial debrief "Thought he had selected crossfeeds open" after the lack of engine response.
This would imply that Xfeeds OPEN would not be initiators of the problem.But also as I remember it was added that one Xfeed was open, but the other was not,(fully open) This led me to wonder out loud if the Xfeed had for some reason been like that the whole time