Update 2/29: I have been quoted a final bill of $14.10.

2/29 UPDATE: I might be in good shape. I only had to speak with 2 people today, which is a significant sign of progress. Best news of all, is that after a long search for my account, the representative said my final balance was only $14.10. That is great news, and I may finally be at the end of this road. She didn't know why I hadn't received the bill yet (she said it mailed 2/16), but that it should be en route. And she had no idea why I never received my two rounds of shipping labels. Oh well, I was hoping to ship my final payment, in pennies, in the largest box I could find at their expense. Oh well. Hopefully the next update is the final one.