Yeah, not much logic that can be used to answer your question. About the only thing I can throw out is that Player B is playing with a Frosh PG and a Soph SG, which could be hindering his ability to get good shots.
Also, Player A is a great rebounder and very well could be getting the majority of his points cleaning up around the basket, which would help his FG%.
Player B should be an offensive stud for DII, though, no matter how you cut it.