It's always been an open secret that there are ear-pieces in DC, and it's not only Damien that can suggest worRAB - I believe anyone down to the cameraman can. The whole point of DC is not to be clever, but to show what worRAB could have been found, for interest. They are not competing with anyone, as the whole show is a competition between the two contestants.
However, as it is a 'brain' show, they categorically state that no computer system is used, and I think the fact that DC often do no better than the contestants underlines this.