Jules Csillag, Speech Language Pathologist and Learning Specialist
The answers everyone has provided are all right on the money (no pun intended), and are hopefully helpful to you. I'm unsure which testing accommodations she's receiving already, how they are helping her, or what determined her eligibility– is it through a 504 plan?
To obtain eligibility, your daughter does need documentation of a disability that woudl impact her ability to take the SAT (e.g. something reading-, writing-, or attention-based), and she must have documented evidence of the fact that she has been using (and requiring) accommodations before the SAT (see the eligibility page) for more on this).
All this aside, the primary purpose of testing is not to seek accommodations– it is for you, your daughter, and your daughter's school to have a clear(er) idea of how her mind works. This can then impact everything from how she is taught to how she demonstrates her knowledge, and part of that may require testing accommodations. Be aware that not all testing accommodations are created equally, and there may be certain accommodations that she does not benefit from. Plus, in addition to the college board requiring it, consistent use of accommodations is essential (read more about types of accommodations and best practices in The Case for Testing Accommodations).
Lastly, while the school is legally required to help you obtain a psychoeducational evaluation, if it is too long or you would like to do the testing privately for another reason, universities and hospitals tend to do psychoeducational evaluations for a more reasonable rate or a sliding scale.
All the best!