A good teacher in elementary can make many accommodations possible.
Here are some ideas
https://www.additudemag.com/iep-accommodations-what-works-for-us/amp/
For my child at that age, the important ones were: allowed to take a break as requested, seating in the from of the classroom, taking big tests in small group (outside the classroom), access to headphones and fidgets.
Does the child need these accommodations to function in the classroom? If that is the case and the school said no, I would write an email giving examples of why these accommodations are needed. If they say no again, make sure it is in writing. Keep track of incidents at school that were escalated because she didn’t have these accommodations.
I am not familiar with DC schools, do they have a parent liaison person to help or give ideas (some parents like PSL others don’t)? I am not sure how you would escalate the request if the school keeps saying no. Good Luck.