In the scene where Preach is in the oven hacking away at the metal above him he is drenched in water, when he leaps out of the top oven he takes out his zippo, lights it and throws it to ignite the gas. As any smoker that has gone through many zippos in their lives can tell you, a zippo lighter is NOT waterproof, even for a few seconds, there is no way Preach would have gotten that zippo to light, ESPECIALLY on the first try.