ADOS test scoring

My 8 yr old has recently had this done and scored 12, we are awaiting diagnosis but they want to observe her a little more first as they have also picked up attachment difficulties as shes adopted and they are pretty sure its both and want to see whats attachment and whats autism as she has a few little things what keep holding them back on diagnosis, although the doctor said shes 90% sure they will be going down the autistic road of diagnosis and this is why shes doing more testing for it to be 100% certain part of me in my head keeps thinking well what if she choses to go down the 10% path and not diagnose, how common is it for a child to score at this level and not be diagnosed, it sounded that they are definately looking at autism and will be sending a report in school to say so but i still keep wondering if anyone could score 12 and not be diagnosed? She also has sensory processing disorder