Mid/rear Seats Assembly problems of the 2014 Ford Focus

Our car Ford Focus 2014 purchased in tracy Ford, CA generates a horrible smell, localized in the back seat region. We've cleaned and scrubbed this area with soap twice, but the smell does not go away. The smell has been there for many months now, starting a few months after we bought the car brand new. It is an awful strong chemical smell. We are concerned because our two small children sit back there in that section of the car. Also, nobody wants to ride in this car because of the smell. The local Ford repair shop confirms the smell but cannot tell what it is. One dealer (tracy Ford) thinks it is chemical from plastic, the other dealer that made us pay 150$ for not fixing anything much, doesn’t know what caused it and will not perform any work other than the basic check because they said it would cost thousands of dollars to take apart more parts than the basic look around check. We are worried about what this smell is, as in is it dangerous or not. We asked Ford 800 number to investigate, but they said the dealer has to confirm that is a defect for them to cover the cost. While the dealer would not perform any further investigation, unless someone will pay the thousands of dollars. So we are stuck with a car that is too stinky to drive, paid 150$ only to be told that if we want them to investigate more, we have to pay thousands of dollars. The brand new car is both too stinky to drive, and too stinky to sell. It is brand new yet we could not drive it. The dealer and Ford are both washing their hands and don’t want to cover the cost. We want the manufacturer and dealer to investigate free of charge and to fix the problem for us free of charge.