I don't mean to come off as judgmental or condescending, but besides writing scripts for a living, I also operate The Script Mentor (www.thescriptmentor.com), specifically to help newer writers from making expensive mistakes (I apologize for making huge leaps and assumptions here). Since I do not know you, I am apologizing up front. When I hear "I'm going to L.A. next month to try to get representation", I become very concerned, and if you are open to some thoughts and suggestions on that front (a "checklist" if you will), you may contact me. It is how we prepare our mentees for any such plans.
Now, about the logline: You had to write a lot of words to make a clearer picture, and I still have questions. The logline doesn't necessarily have to tell ALL of the story, with every nuance and twist, but we should have a GOOD IDEA of the story just from reading it, and have our imagination fill in the holes.
The good news is I sort of figured out the general plot from your original logline, which supports my opinion of it being "a good start". The problem, I think, does lie in the plausibility of the plot. I'm not understanding why his mentor- the actual killer- who's goal is to expose the true existence of werewolves, not just expose the detective for being a werewolf? Or are you saying that the killer is making it seem like there's a werewolf, but doesn't really believe in them?
Lastly, your protag is in conflict: to either spend his life in prison (or be executed) or choose to expose himself as a werewolf, and somehow try to convince people he's NOT the killer? Seems to me, if he exposed his wolfness, it would only go to stregthen the case against him.
Plausibility is a huge issue in many stories, so don't feel as though I'm picking on you. I'm not. With this confused (at least on my part) plot issue, the logline can't be any better than it is, IMO, and yours will be as good as anything I could possibly suggest. I'm all about helping, but sometimes even I get tapped out on ideas that doesn't include major changes.
Geno Scala (sharkeatingman)- judge