P0016 Fault Code on 2007 VW Passat 2.0: Causes and Solutions After Timing Belt Replacement

I recently had my timing belt replaced, but the mechanic had to redo the work because the first attempt was subpar. Since then, I've performed a full tune-up including new camshaft sensor, temperature sensor, spark plugs, and coil packs. Despite these changes, the car continues to display fault code P0016 — indicating a 'Crankshaft Position - Camshaft Bank 1 Sensor A' issue. The official explanation for this code is typically either a timing belt jump or a failed camshaft position actuator. Possible causes include: - Failed camshaft actuator - Blocked oil passage - Faulty crankshaft position sensor (though I haven't replaced the crankshaft sensor) I've already checked the CKP sensor and confirmed that oil levels and circulation are normal. The issue persists even after replacing all major components. I'm looking for reliable advice on how to diagnose or fix this specific P0016 error in a 2007 VW Passat 2.0 with a 2.0L engine. Any insights would be greatly appreciated.