I find it quite odd that you could keep you "fake" lies and your "truths" straight on a few hours of sleep when you couldn't even keep your story straight posting!

For example you say:

"I recently applied for a job in the private sector, to do with a high-level security position, related to contract government work. I won't say where, and I won't say exactly what type of job it is, as it is unimportant."

and.........

"I know it wouldn't have disqualified me from getting a security job in the private sector"



You did fill out a job application correct? The examiner reviewed your application, correct? On the application you answered many of the same questions the examiner asked, correct? Did you lie on those too.? Or did you answer truthfully?
If you answered truthfully then the examiner could have compared notes and easily seen you were lying on your questionarrie even before the test began.
If you did indeed lie on your application you forgot to mention it here.
Either you had one dumb, unqualified examiner or your story is a bunch of sh#+!