Could have been anywhere over Belgium, The Netherlands or Germany. Standard procedure if comms are lost. There are technical reasons which have been covered many times in these forums which can lead to inadvertant loss of comms. Not always a case of pilots sleeping. On the other hand, and I'm NOT saying that this was the case here, if you're flying through busy North European airspace and you hear nowt for more than 5 minutes, you should be asking yourself questions.
I hope the Eurocontrol quote is untrue. Quite pathetic if so.