
It took really some time but what I can say to all of you having troubles in a similar case with easyjet baggage claims, is: DON'T GIVE UP.
So I recently got a cheque from easyjet with the original sum of money I claimed. Before, I had to go through the same process of identification as it is described in this blog here.
I sent all the correspondence by registered mail of course but I wasn't backed up by a reference to any consumer defence agency. So keep on your case, the law is on your side! Easyjet should pay at the end...