I'm not sure exactly how they could use it in court if it's sealed. Their contention is that the report is accurate, and the defense would need to be able to refute it. I guess they might ask for a closed courtroom. Of course the Justice Dept opposes their request.
Yosemite’s ex-concessionaire wants details of disputed appraisal kept secret
http://www.mcclatchydc.com/news/nation-world/national/article68801787.html