Advice needed

Hi Everyone,

I am looking for advice to help my 6 year old non verbal son who refuses to go outdoors.

This all started 3 months ago when he started refusing to go to School after developing extreme separation anxiety in the mornings going into the classroom. The last few times he had to be carried in by a teacher kicking, screaming and hitting. We have been told after various meetings with the school it would take him up to 2 hrs to calm down. He then refused to go to School having massive meltdowns, hiding away in the house, hitting us and throwing objects at us. When carried to the car he would undo his seatbelt in the car and try to get out, even climbing to the front and grabbing the steering wheel making it unsafe and impossible to leave the driveway.  When asked why he doesn't like going to School he just says "too hard" , doesn't like dinnertime due to the canteen smell and "too noisy". Just the mention now of School, colouring in, looking at books, or being told of one of his classmates or teachers names causes him to get extremely upset. Myself and other family members are told to stop talking or go away. Grandparents can no longer visit the house or friends, He won't let anyone sit next to him on the sofa, we are told to go away then pushed or hit, and if his siblings enter the room making too much noise he gets aggressive shouting for them to go upstairs and has a meltdown. His daily routine involves waking up and turning on the TV to watch his favourite programmes which he watches all day long, when he gets excited he jumps up and down raising his hands above his head which I believe is his way of stimming. He has now broken the sofa due to the constant jumping up and down in the same spot. He now sleeps on the sofa refusing to go upstairs to his bedroom. We have tried turning off the TV for short periods of time which results in massive meltdowns and he then covers himself with his blanket and hides away, withdrawing himself from everyone. It is like he has made himself his own safe space around him which no one can enter. He is eating and drinking and looks happy, sometimes laughing at the TV. He will only let us clean him with wet wipes occasionly, refuses to clean his teeth and spends all day in his underwear refusing to get dressed. My partner and I have had many meetings with his School speaking to the head of Senco, His specialist speech and language therapist, School psychologist, and his teacher from his specialist speech and language class. We have also contacted local Mental health bodies, His doctor and have now reached the end of the list of people who might help in trying to figure out what has triggered this or what might help him. Due to the difficulty communicating due to his limited vocabulary although he can understand perfectly when asked a sentence, We are now at a loss for who to ask for advice. Can anyone help with any previous experience of this?, has he had Autistic burnout?, should we just let him keep watching TV all day in the hope he will eventually go back to normal activities or will we cause further withdrawal by removing his favourite stimulation?. Is it safe for us to just turn off the TV without affecting his mental health? and does anyone have any suggestions to try to get him back to his normal self wanting to go outside, play on his scooter and go to the park like he used to. He used to be such a happy boy and loved outdoors but now with him being like this we can no longer go out as a family together. Work hours are affected and also daily routines like school runs or shopping due to him not wanting to leaving the house. Myself or partner always has to be home and it is beginning to feel like a prison.

Sorry for the essay but we just want some help and advice for our son to get back to normal.