Sand - the apparent dire state of the competence of the 'seniors' at the time and the apparent lack of airworthiness of the Mk II is indeed very important, but it should not be forgotten that the Nimrod also joins that sorry party, as probably do several other at present unknown service types.
The scope of this is really is vastly outwith the campaign here. Agreed, of course, that it helps the case somewhat, but even if it was 'fitted' or 'carried' it needs to be shown that the assassination attempt took place for it to have a real bearing on this crash. I doubt that and I see no evidence to support that.