After enough reverse engineering, enough reading of the API docs, enough flat out guesses (most of the real work was this), and enough debugging lines in the OpenSRS supplied libraries, I figured out my problem. Not only did I solve the authentication problem but I went on to figure out why my domain modifications wouldn't work.
This process was so frustrating that I'm completely worn out by it. I want to take a nap. Instead, I'll just take an early lunch and hope I can snap back into it soon. Reverse engineering the code and the docs is not a fun thing. I was reminded of the scene in Office Space where they were so frustrated at the 300k in the account all they could do was curse and well... curse. I refuse to feel like Michael Bolton though.