You're not handling line items with quoted strings correctly. The following lines were not included in the output QIF file.
Any line item with "Smith, Herbert MD" or "Katchis, Stuart MD" or "Howanitz, Nancy MD". I was wondering why these weren't making it through but other healthcare items were, then I realized these were all doctors that I had as last name, first name.
Also, line items with amounts greater than 999.99 aren't making it to the QIF file because Excel has them as 1,234.00 so they get quoted. I suppose I could have changed the format to not include commas but that was not an obvious problem beforehand.