When I first was hired 12 years ago, my manager refused to provide me interpreters for training or meeting. It made my job much much harder, even with email/summary notes.
I hired a lawyer back then, they said they are required to provide me reasonable accommodations such as TTY, interpreters, etc upon request. It took me nearly a year after manager to finally provide me accommodations after I threatened to resign my job. (I was only person in the office that can perform many advanced tasks that many people couldn't do or do it quickly.) To this date, he still do that accommodation without too much troubles. It is usually in their best interest to keep valuable employee happy in long run.
Mortal of the story, if employer think you are valuable employee, keep fighting what you believe you need to do your job.
