Hi Chris,
You are permanently locked out. Apple doesn't understand how their software works which is why you got the above response. (I'm not sure that anybody at Apple has ever seen a computer.)
Like you, I cannot access the itunes store to deauthorize former dead computers -I get the same error as the program crashes. Nobody knows why this happens. Apple doesn't test software anymore and they don't answer any questions. They just hope that you go away.
They do hope to sell you a car someday. If you're sucker enough to buy one you'll get the same treatment.
It's really too bad. A few minutes of understanding the software and providing support to users could go a long way. Not at Apple though. Just hand out generic untested instructions and hope that people just go away.