Mobility for mental health

Hi, could anyone advise me please? I put in a mandatory reconsideration fir my adult son, as I think he us entitled to higher mobility for pip. He is at the moment on high care and low mobility. He has ADHD, anxiety and depression. He never goes anywhere without me or my husband. He has been like thus since a child. He is now 30. Even when he went to college, qe had to rake him. Wont even go to the local shops. I go to the GP, and the shops with him. He has severe anxiety and also the ADHD, prevents him from going out alone . He would never be able to find his way, even if he is familiar with it. He wo t even go in a taxi on his own, because he us to anxious to talk to the taxi driver. They refused him on the mandatory reconsideration, so I am now going to appeal. No reason was given, apart from he doesn't match the criteria. Sorry for long post. Angela.