Customer blames Manufacturer

I cleaned a carpet in a house that was only 7 months old. Granted, the carpet was abused through day care conditions. The carpet was an inexpensive HomeDepot carpet, mid-length coarse shag, made of recycled plastic. Some of the fibers seemed to have broken down and intertwined themselves to the base of their niehboring fibers. The customer thought that the traffic area still seemed dingy even after I extracted the entire area with the U-mate. I then explained and shown her the above explanation. She then called HomeDepot to come and inspect. They said it was normal wear and the cleaning process was inadequate. She then had the inspecter visit with me on the phone to qualify our process. I explained that I used a dual method of water extraction and the bonnet method. The manufacturer will not stand behind thier product so, she wants me to create a letter explaining why I feel the carpet is defective. She then wants this to use in small claims court. I feel that this is not my problem and I’d rather not get myself or the Heaven’s Best name involved. Please send some advice on the delema. Cody, is this an action against our contract or legal obligation?