Hospitalised PDA child

Please help! My 12 year old has had an autistic shutdown with severe PDA, low mood- severe anxiety, angry dysregulations, no self care for 4 months ( same clothes since admission, no brushing or bathing) on a hospital ward under CTO, unable to take medications or engage with any psychological interventions. He has become non verbal in hospital, communicating with typing only on Ipad. He is unable to clearly describe his emotions but is clearly depressed with extreme negative thought ruminations. 

A high achieving, regular school attender in primary but this year with transition to secondary school, has experienced bullying at school and refuses to attend- terrified about online schooling too. Stuck in hospital and his anxiety is worsening about not being able to go home. Community Teams feeling worried to let him home as he needed a very traumatising regimen of multiple sedative intramuscular injections to get him to hospital. I have informed the MHO of the situation but no one seems to have a clue how to move forward.

Any thoughts and suggestions about what I can do to help my son, is most appreciated.