I have lots of thoughts, but it's late, so I'll focus on one. You sound frustrated with the school for not providing your DD more challenge, and I'd encourage you to think about what you want for your DD, do some research, and advocate for some specific changes. Would you like her to accelerate to a higher grade level for reading? Would you like her to do independent reading or online work during part of reading time? If you are uncomfortable with her being a helper, communicate that to the teacher and request that she not be placed in that role again. Hopefully others on this site will have some good questions or thoughts that will help you shape what things you'd like changed for your daughter. Given the questions you've already asked the teachers, and their vague answers, it sounds like you need to go in with specific requests, and specific information about her skills to back those requests up. Some teachers have the desire and energy to listen to your general concerns and work with you to develop a plan of action; others need parents to make very specific requests before they will act. Yours sounds like perhaps the latter.
One other item, regarding testing. You know she's gifted, regardless of testing. Many school districts don't accept outside testing. If that's the case with yours, spending that money even if you had it may not bring any different results for you. Both of my DD7's teachers (K and 1st) have seen his IQ testing, which we paid for privately, and I don't think they even know what those scores mean. What they understand is the parent explaining the child's skills and abilities and requests for specific accommodations that meet those abilities.
