I have 2 brothers with Apergers and 1 with moderate to severe autism (and other conditions as well). My brothers with Aspergers (HFA/mild autism) had assessments that took about 8 hours or so over 2 days. My parents had these big packets to fill out before the appointments and the school had to fill them out as well. The people assessing them had them complete some tasks with blocks (colored blocks and trying to copy a sequence), matching, receptive and expressive verbal abilities, memorization, modeling and then doing some tests on paper. They both hated it. My more severe brother is almost untestable.
The school does not want to be bothered by having to provide supports and you want all the supports that you can.
I know my brothers with Aspergers were upset by the diagnosis but when they got the diagnosis they were able to recieve services in the USA via the Americans with Disabilities Act. They got the help they needed. My mother was VERY upset when my younger brother was diagnosed but we knew something was wrong from the time he was about 18 months old so while she was upset they at least had a name and could begin therapy.
If the school says she has no problems then this is very simple at least here in the USA. You video tape her. You get a psychologist to back you up and you video tape her. If they won't let you do that then there is a problem. We video tape all of my brothers (and actually another brother was suspected of having it because hes a little geeky but his diagnosis was that he was basically just geeky) and then my parents and their learning teams assess their progress, regressions (if any), areas to work on, areas that are about as good as they will get etc.
It is overwhelming now I am sure but just wait until you get it all finished. Tell the doctor you believe the school was not forthcoming and that you would like your daughter video taped.
3 brothers with ASD
I tutor autistic kids
I work in an autistic summer camp
I volunteer in an autistic summer school
I am active in our local autism group