I just bought a used couch that has a dog smell to it. I am in the process of cleaning it and I am wondering how to clean the couch back cushion stuffing. I have very little knowledge of couch anatomy (?) but I believe it is filled with loose polyester stuffing. (See attached photos). Also, one of the lining bags that held the loose stuffing was torn up, so I had to throw it away.My questions are:1. Is this indeed polyester stuffing that I have?2. If so, is it possible to wash/clean it, and how?3. What is the white lining that holds the stuffing called, so that I can buy a replacement? Or any suggestions on what I can use in place?Thanks.