From what I read Meredith was killed in her room, They claimed not to know where she was, faked a robbery and called the cops who found Meredith murdered in her room. It would be incriminating if all of the blood were in her room since they claimed not to know she was in there. Wouldn’t prove she did it but would certainly cast doubt on the story she told and would be incriminating.
she could also have been an easily panicked ditz.
Only a guy can judge the ‘maybe it will look like a crime scene’ thing ; )
I don’t think the truth will ever be known by the public. Too many botched forensic/investigative techniques to trust any of the stories that came out.