As Gordon and his co-authors express it, accommodations are outcome neutral. A few points, the IEP or m504 Plan is no longer a legally-binding document under a different part of 504 or the ADA so those plans do not verify a disability. You will need to submit documentation to SAT, ACT and the same information will be needed by college disability services to register for accommodations. Your child with a disability has become an adult.
Looking at CC, lots of students freak out, shut down, space out or something in, have test anxiety, run out of time, can’t remember what they no, etc. Any number of problems taking these tests have difficulty beyond what may be typical, But problems with processing speed, time management, anxiety, etc. must reach the level of disability through clear, compelling documentation to merit accommodations.
Thank you for reading if you even get this far!