Good eye! That's indeed a typo in the notebook. Somehow in the actual design I have the correct pairing https://github.com/newhouseb/onebitbt/blob/master/onebitbt/r....

Since writing this particular notebook I've actually built out a proper CORDIC module, so once I get back to the environment where I was writing all this (I am nomadic right now w/ anemic compute) I can fix this and rerun things (and add in my CORDIC implementation).