BEagle,
Having read the Argyll new report you helpfully posted, I scrolled down and read the comments. I have to say I was somewhat surprised by the last few. If what is written is true, it suggests that a whistleblower has come forward to claim that it was an inside job.
I've been following the thread, and if I didn't see it raised here. Apologies if it already has been.
Without more information, purely hearsay, but as has been mentioned before, a plausible scenario.
TN