Hi Amy,
Glad you got information you feel confident about. That's a wonderful step.
Why a 504 instead of an IEP? Usually people with this range of disabilities will benefit from special education services at school.
Did she give you treatment/therapy suggestions? We have seen great improvement with DS through targeted therapies.
FWIW we were told by a neuropsych that as you remediate deficiencies, test scores can change a lot, typically becoming both higher and less spiky.
Kudos to you for seeking good information to help your DS!
DeeDee