my children, now adults, are autistic. Only my daughter completed school, and they weren't diagnosed until they were adults.
I would say the things like the hair may just be what they feel they have some control over ( and can explain to themselves) it wasn't until post 16 mine were able to explain, and understand enough, the pain caused by the school uniform, by noises, smells, tastes and texture.
Secondary school is all very well, I am now a school governor, trying to make change, but they have their rules and policies, and either they make allowances which leaves the kids open to being bullied or won't make the needed allowances (some which you and your grandchildren may not even realise they need to be made).
My children were never happy, or settled until the pressure of having to conform was removed and now in their 20s manage to live a live that they can manage but i struggle to understand. (in rooms all day, sleep to their body needs not needs of a clock etc).
My cousins were both diagnosed as young children, they attended special schools etc but really as adults their lives are not much different from my children, except one still lives in a residential complex.
Its very hard as my son is an excellent musician and artist, and my daughter is skilled at woodwork and building stuff , but neither wants to make use of their skills because they can't cope with people and the outside world.
I think what I am saying is you and your daughter may have to just go with what the children can manage, they my find a school unbearable, they may, or 1 might, prefer a special school, or maybe they will just need to be supported to be themselves which may mean stepping away from what we consider normal. PS CAMHS were hopeless!