Hello Appletart,
I would ring the DWP since you are right, claiming that you use an aid which you do not, could be considered fraudulent. Do stress that he has mental health issues, and panicked when rung up out of the blue, and I cannot imagine there being any comeback on him. You really don't want to wait, find he has been given an award on the basis of false information and then have notify them and try and turn back the clock.
However, if he is blind I would be surprised if he does not use an aid of some description when he is outside. It could be a stick or a dog, but it could also be the arm of a friend or a wall which he runs his hand along, or it could be a friend’s voice as they make him aware of his surroundings and potential risks.
I hope he soon gets the right award.
Catherine
Nothing on this board constitutes legal advice - always consult a professional about specific problems 
