Stacie,
Right again, Stacie. If the faculty member is given extraneous information about the student's disability, it may lead them to speculate about the necessity or appropriateness of the assigned accommodation. That decision should be left to someone who knows the full situation (including the legal end of things) and has full access to the student's file. In other words, the disability service provider assigns the accommodation. The faculty member just needs to help make it happen.
Dr. Jane Jarrow