The crankshaft and camshaft position sensors work together through a timing belt or timing chain (depending on vehicle model). I'm guessing here that probably what happened was that a mechanical fault or an issue with the variable valve timing (lack of oil and seized of camshaft) told the computer that the camshaft was not in sync with the crankshaft and it triggered the code. Many vehicles have interference engines, meaning the pistons and valves have to work in a predetermined sequence, synchronized by the timing belt or chain. When they are out of sync (for example, camshaft stops and crankshaft keeps rotating), the pistons will hit the valves, causing severe damage to the engine (bent valves and/or pistons). This is how the engine "explodes" or is destroyed. It's possible this is what happened to your engine if the timing belt slipped off or broke, or a problem developed with the camshaft.