If it was faulty the car would start and then cut out straight away. The immobiliser does not stop the car starting but cuts out the fuel pump which is why the car won't run. To check out or remove the immobiliser you would need the car started anyway. Your fault is not immobiliser related IMO. A fellow member on here had a similar problem a while back where he sent weeks looking for the reason his car would not start. In the end he found out the ECU earth was faulty....changed this and away it went.