The letter clearly states he has contacted every Amazon support option he knows of:

  I have filed a complaint with the BBB, emailed everyone I
  could at Amazon, called the Customer Service Line, the
  Kindle "Executive" support line, and Corporate. I have 
  been apologized to by everyone I have spoken to and been 
  told that they have never seen this situation before.
 
  None of them can tell me if I will ever receive the 
  content I have paid for.