Hi everyone, I am a long time lurker with a few posts here and there.
If you are in the US, they have to follow the IEP accommodations. He may need to be tested after the other students so that he is in a small group.
If they wrote the accommodation then they clearly feel he needs it and he is entitled by law to it. They don't need to purchase special equipment, they hust need to adjust the schedule of computer lab time. In my middle school thats how we handle the small group testing, they take it at a different time of day only with the other few who have this accommodation.
I would state in writing that you expect your child to be given all the accommodations in accordance with his IEP so that he can do his best on the assessment.
Sounds like a logistical issue on their part. Tell them "too bad, so sad" and wave the IEP, the "legal" document in their face.
Ugh I am dealing with and hearing so much about schools and districts hoping that parents don't know their rights.