Hoofharted
Even some experts in London are suggesting it could have been windshear. Aircraft at the time were apparently experience wind changes below 200ft with the associated variations in IAS. I personally haven’t experienced it in LHR but I have in HKG and NRT. Luckily for me we knew it was coming and it was positive windshear, not negative as it appears likely here. What I have experienced at LHR is wake turbulence below 200ft because of the 3nm separation they use there on final. I was flying an A340-600 and we were following a B747-400.
By the way, how do you think the investigators initially start the investigation? They use experience and evidence to deduce (speculate) the most likely cause so they can direct their resources in the most economic direction.