Omega B – X20XEV – Unknown engine problems

Hello again After my Omega finally has TÜV, a new problem had arisen. Yesterday we drove to the workshop because he lost oil. On the yard, waiting for a moment. Mechanic comes, squats in, wants to turn on, but does not want to. Pushed in, diagnostic computer connected. Results: camshaft sensor. The oil problem was the valve cover seal. Now the workshop called today and said, the camshaft sensor is changed but he does not really want to start. After some attempts he starts again willingly, if he wants to turn it on again, it does not work. Battery is ok. He meant now that he wants to try another sensor again, if the new one is in the bucket. He also wants to call a Opel workshop again in the hope that one still has the omegas in his head. I told him that I will ask you, because the omega density should be quite high. Does the problem of one of you, what could it be? What would be typical of the omegas??