Wow, congratulations!!!!!!!!!!!!!!!!! Very impressive story
I contacted FitnessQuest once, regarding a part for my Total Gym, and they also gave me a hard time. They didn't care about the info, it's just that they no longer make the bigger ones like I have, someone else does them. However, I bought mine in 98 when they DID make them, so they should still be responsible for parts. (the new total gym 2000 maker refused to help me)
I kept insisting, and then demanded to speak with a supervisor. I was not asking for a free warrranty replacement item, I fully intended to pay for the part. I finally got someone that would give me the info and address to send money.
It's been a real pain, so I understand exactly what you are going through!
Have you spoken to the relative that gave it to you? Maybe they had it sent to an alternative address at the time of the order. Or maybe they purchased it at a retail store, etc.
Even still, if you registered the item on your own, and provided your own address, that is all that should be needed. I'd ask for a supervisor. (I used to work in customer service, asking for a sup usually gets you what you need)