Hi Waxwing
I think his best bet is to send a corrected sheet or statement to DWP.
Make sure he clearly shows his NI number, name and date of birth in the correspondence as well as any reference number. Keep a copy.
If you are assisting your brother to cook, a letter from you stating that will be useful.
If your brother uses a perching stool or other aids then make sure these are mentioned.
Hope this helps
Regards
Pete
Nothing on this board constitutes legal advice - always consult a professional about specific problems