Flight Safety
Not a bad suggestion. I'd guess it would be comparatively easy to do a test to find out where any vacuum induced temporary buckling/collapsing of the fuel piping might occur. Those locations could then be investigated on BA038.
But getting back to the main problem that remains so elusive: Could it be worthwhile to look at the facts from a 180 degrees opposite angle? I.e. perhaps the problem was actually too good fuel? Factually, large numbers of B777s operate sucessfully every day on fuel that freezes already at -47 degrees. Could the fact that this fuel was good all the way to at least -57 degrees cause some indirect effects that eventually led to the fuel starvation problem? What about the water content in the fuel, will it behave differently at such low temperatures?
Just my layman's $0.02.