Valeo clutch Kit. 1 year guarantee a excuse

My mechanical company supported Kotwals Kempton park for 15 years + but now a days they buy cheap import part for more expensive. With 6 chain engine (all of them engine must come out) were I bought G tech gasket sets. once I idle the vehicle in between head and block water was bubbling out. Later replace with Victor Reinnz gasket. problem solve. When I speak to kotwals they just shake there head. Lost all that money and time. Couldn't charge it on my clients. The last straw came now. Bought a Valeo clutch kit for Toyota Corolla 2001 that carries a 1 year guarantee. (The easiest to work on) My client drove his car for 3 months when he phoned me he do not have clutch. Takeout the clutch to my surprise the clutch plate snapped the middle part from the out side part no burning marks on clutch at all. In my 25 years as a Mechanic never saw that. send it back. After testing Kotwals Kempton Park came back to me to say rejected apparently the clutch was misaligned. After all my years experience and years of supporting them I'm dumbstruck