You can sue in Norway, Germany or Switzerland then.
I'd use the German ombudsman if I were you. It's free and has a good reputation. SOP I think it is called?

Even though Norway and Switzerland are not in EU they both are signed up to EC261. However I know the Swiss Courts are much more generous to the airlines than EU member state Courts. Hence why I'd recommend pursuing this in Germany as its an EU mender and the EU takes a very generous stance to the passengers.