Have you had a meeting and they determined she didn't need accommodations? Or you haven't even had a meeting?
I thought under Federal Law the school HAD to set up a meeting within 30 days of written request from a parent.
I do see that until they put an IEP in place, they can't make accommodations. They HAVE to treat her *just like every other student*. It's frustrating.... but it will completely throw off the IEP process if they provide accommodations without an IEP in place.
Sitting alone at lunch, though, seems extreme. Is that in their code of conduct in the school handbook as a possible consequence? If not, I would request in WRITING from them why they are doing that and what they hope to achieve.
Does the school have the "official" diagnosis paperwork from whoever provided you with a diagnosis? Can they provide IN WRITING accommodations they request? That may give you something to IMMEDIATELY put in place until you can get a plan put together.
I know when we did my daughter's IEP, we were allowed (but not TOLD, so if you didn't know this.... you just didn't know) to have a Child Advocate present. This would be someone with experience or information about your child.... for example, her pediatrician or if she is already working with a therapist. That also may help your cause.
Also - a social worker was OPTIONAL for the meeting. The parent has to request. Please make sure you ask for these things that not all parents know are available. I would think a social worker would do wonders for addressing the social aspect of your daughter's accommodations.
My daughter scored quite high in anxiety for her IEP testings.... so much so that she was provided an accommodation in that area (I guess you aren't always...... ) anyway one of her accommodations was to leave class and act as PE helper until she could get herself *under control*. We worked with the PE teacher (who had a special ed certification.... that may have helped) who would have her do things like run and get the balls from the locker. Or give everyone a high five..... things so that she could get her energy flowing and get her mind of whatever was building. That did soooooo much for her.
It's a shame that your school is not being more cooperative. I would not give up.... but definitely get EVERYTHING in writing.
Good Luck.