Well instead of trying to figure out how he did it, it can be effective trying to find something that could prove he is innocent. There is only a handful of those left, and they sound increasing less likely every hour. I in no way think Brian is innocent, but evidently, the police don t have enough to charge him yet either.
I know he isn't the sharpest tool in the shed, don't think he has the resources to flee the country, but I have a hard time thinking he is camping out this whole time either.
One thing that puzzles me, what is his story gonna be? Is he gonna say he wasn't with her, he left and somebody else killed her? He had plenty of time to bury her why did he leave easily found? Did he just panic?