Am I wrong in thinking that Boeing & RR are providing resource to the AAIB? If they are, are you suggesting that there are people here who know even more than the manufacturers?
No, in answer to your question.
My original point was that speculation/hunches as to the cause of an accident should always be very welcome on a forum such as this because there are many pilots/engineers/scientists with very varied and broad experience here who can make a genuine contribution - look at the 777 thread as an example. There is no way that the AAIB can solicit that breadth of voluntary contribution from its limited field of experts and linear communication with them. That is why open forums like PPRUNE should always be encouraged to speculate as to the cause of accidents.