status of a "working diagnosis" plus Q about attachment disorders

Hello,

I'm a newbie to the boards. I have an 11 year old daughter who has a working diagnosis of "High Functioning Autism with possible attachment disorders" from CAMHS. The problem is that social work refuse to treat her as a child with an ASD until there is a full, formal diagnosis. Is this correct? I would have thought the purpose of a working dx was to say, treat this child as if she has this condition unless advised otherwise?

Also, Social Work do not have an accurate view of what "possible attachment disorders" means for a child on the spectrum. They are taking it to mean traditional attachment disorders which are the result of erratic love and attention in early childhood. Does anyone know any good sources of information for me on attachment disorders with ASD?

Thank you in advance,

Rosie