Warranty on company fitted tyres?

I recently bought a Fiat Punto Car on 31March 2014. The tyres on the car are Good Year Duraplus. One of the front tyre of the car was dammaged. The tyre was rendered irreparable as the wall of the tyre got holes. I visited Fiat service and was told that I need to claim for insurance and would get 50% of the cost of the tyre. I calculated and found I recently bought a Fiat Punto Car on 31March 2014. The tyres on the car are Good Year Duraplus. One of the front tyre of the car was dammaged. The tyre was rendered irreparable as the wall of the tyre got holes. I visited Fiat service and was told that I need to claim for insurance and would get 50% of the cost of the tyre. I calculated and found that buying a new tyre would be cost effective. (50% cost + insurance fee + no claim bonus + two days in service center). I went and bought a new tyre Good Year, however a different model. The tyre dealer informed me that the tyre model that came with the car comes with a warranty called WFS (worry free warranty). In the warranty, wall damage is also covered and Good Year replaces the tyre after deduction on the tyre usage. When I contacted Good Year. A engineer from Good Year visited and checked the tyre. He rejected the tyre with the comment, "No manufacturing defect." However, the engineer informed me that if I had purchased the tyre from a tyre dealer, I would have got the tyre replaced. My question is, if a product is available in market. Do different warranty poilcy apply on the product, if purchased from different sources? As when i contacted Fiat they directed me to Good Year and they informed that its a promotional offer and not vaild on OE products on the car. buying a new tyre would be cost effective. (50% cost + insurance fee + no claim bonus + two days in service center). I went and bought a new tyre Good Year, however a different model. The tyre dealer informed me that the tyre model that came with the car comes with a warranty called WFS (worry free warranty). In the warranty, wall damage is also covered and Good Year replaces the tyre after deduction on the tyre usage. When I contacted Good Year. A engineer from Good Year visited and checked the tyre. He rejected the tyre with the comment, "No manufacturing defect." However, the engineer informed me that if I had purchased the tyre from a tyre dealer, I would have got the tyre replaced. My question is, if a product is available in market. Do different warranty poilcy apply on the product, if purchased from different sources? As when i contacted Fiat they directed me to Good Year and they informed that its a promotional offer and not vaild on OE products on the car.