Non starting au3 wagon

[El Venom]

Hi. This I a bit of a long one.

I was helping someone out by swapping a starter motor out on thier au3 wagon. The car stopped running one day, was towed to a mechanic who did something around the ignition barrel and then said it was the starter. I fitted a 2nd hand starter for them as the mechanic had already charged these people over $500 and obviously the starter made no difference.

The dash, lights, fuel pump ect do what they should but car won't crank. I managed to connect a laptop to the car and using forscan found the car was immobilised. It also says no keys paired and that there is a eec communication fault related to the cluster amongst other sensors like fuel sender not working and ac and ps pressure faults.

My issue is how do I get the car started again. It has 2 non genuine keys the car was using prior to the vehicle stopping and forscan just keeps telling me programming has failed. This is for an elderly couple in a little country town and they need there car running asap and the local mechanic has already taken too much of thier money