Great idea DeeDee. If the evaluator is not a good advocate, I would consider bringing a parent advocate (which is often much less expensive) to the meeting. A good advocate can understands the testing, law, group dynamics and politics and can be a great resource at these meetings. Often her or she can help level the playing field a bit.
I'm not sure if you realize, but there have been some favorable changes in 504 as it relates to qualifying for accommodations. This article may be helpful (it was for me!)http://www.ncld.org/on-capitol-hill/federal-laws-aamp-ld/adaaa-a-section-504/section-504-in-2009
