Why would the customer wait a couple of weeks before contacting her insurance company, and why contact them first before contacting you to see if the problem could be sorted if she had any intention of getting the stain removed, sounds to me like she was after a new carpet full stop.
I had one customer who wanted me to write a letter for her insurers stating that the carpet couldn't be cleaned without seeing the job, when I replied that I wouldn't do that I was asked to go and quote the job, which I did and removed one part of the stain as a test.
The customer wouldn't accept the quote (which was a minimum charge job anyway) and asked again if I would write a letter for her insurers, when I said no as the stain would come out she got quite verbal, stating that by removing part of the stain I had left a clean patch on the carpet (hardly surprising really, call a carpet cleaner and they might just clean it
), the end result was she called in someone else who wrote a report for the insurance and the carpeting throughout the bottom of the house was written off, she got a holiday on the procedes and the carpet was cleaned by someone else when she got back, hey ho.............................