Can anyone advise:

I have taken two pre-employment FBI polygraph examinations and my conditional offer of employment has been rescinded as a result.  I "passed" the first test but was called back (by headquarters) to take another due to suspicion of countermeasures.  Of course I "failed" the second for the same reason.  

I am following the proper channels to appeal this decision.  Does anyone have experience in this situation, ie, what are the odds of being granted another test, and more importantly, what are the odds of headquarters ever accepting the results of someone that they have already branded as a cheat?

What an absolute dream killer this unethical machine is.  What can you do?  If you get another chance, are you supposed to just sit there and listen to the ridiculous control questions?