from what i understand the concorde was a result of numerous factors, overloaded, Shim missing from UC assembly allowing it to shimmy and create a brakeing force, causing the aircraft to pull to the left, which resulted in the capt rotating below safe speed, and the FE shutting down an engine at the same time..
The fuel leak, i am to belive is not uncommon after a tyre burst, and once the fuel has drained the fire extinguishes. so it was possible to continue to fly and safely return . i am under the impression the metal strip did not cause the tragedy on its own.