Im really not a fan of the 'I know better than the creators" attitude and appriach. I mean, if its made clear (novelization) that Bishop II was human, thats so he is. Yeah, Anderson took an opposite appraich and made a movie implying Bishop II wasnt human but a copy of Mr Weyland. But if you ask me, that isnt valid - it is what it is - a MISTAKE or MISINTEPRETATION, or even better - lack of research. Its just plainly wrong thus its not canon. Saying otherwise (that Bishop II weasnt human cause its not stated in the movie or whatever) is just covering your eyes . The answer WAS given. And given a long time ago