I am curious what the fare calculation on OP's ticket says and if they will go by that.
As far as EU261, my understanding is:
1 - they need to take care of you
2 - you are not entitled to compensation if they take care of you
3 - you might be entitled to compensation if they don't take care of you
So, if you can't get through on the phone and take care of things yourself, I am not sure how that would work.