Since this is a PCA with a solo officer recounting his own investigative summaries, I am guessing the DM used the word "bushy."
People use it in various ways. She only caught a glimpse of him. His height and sex were as important as the eyebrows, but obviously, someone with non-prominent or very thin eyebrows wouldn't fit very well. To her, they were the main thing she noticed in her brief glimpse of his partly masked face.
The idea is that the officer who writes this can be asked to come to court for the PCA process and judge can ask him/her what precisely was said. That was likely not needed in this one. More than enough there, with or without DM's eyewitness account.
The footprints in the blood are great evidence, but the DNA on the sheath is of course what pointed directly to BK.