I know couple of very similar cases.

Once Autobild got involved and it helped, PAG was paying the engine.

Another friend of mine had the same problem and got the engine payed, but not the labor. A second friend got everything paid with 56.000 km. Both have been in Germany. A third friend from Lisboa got nothing paid, cost of around 20k Euro occured.

I would talk with PAG, if required with the CEO itself. Further on, I would involve any press.

This is totally insane if a car which was maintained by AMAG have a blown engine after 80.000 km.