Welcome to the forum.
It should be just a coincidence, unless they somehow managed to jerk/pull the wires of the sensor. The sensor is on the side of the motor whereas they should have only dealt with pulling the upper manifold and loosening a few bolts on top to get at the plugs and wires.
Here's picture of the camshaft sensor. Look for it on the right side of the engine near the top as you stand in front of the car. Check the wires and connection as much as your can.
