The experts who had days to examine the wreckage would have concentrated on looking for evidence of an explosive device in the first place while waiting for the results of the analysis of the FDR and CVR. No confirmation of external cause has come from the Russians, Airbus or the Irish authorities who are in the loop. The first claim of a bomb came from Metrojet in a press release that was aimed at stopping examination of their operations. Now the UK government has stopped all flight to HESH claiming it was a bomb and flights there are unsafe. If there was such clear cut info would not the Russians and other EU carriers stopped flights. As far as I am aware there are no British AIB people involved in the investigation.