I can't access the article right now to double check the detaiils of where the brick was found, but it's possible the door was shatteres while the women were at the wake and the house was empty I imagine they were very tired and when right to bed, so the broken glass and brick went unnoticed. Burglaries are pretty common after a death. Sometimes whole neighborhoods are hit because perps figure neighbors will be at the wake or funeral. The perp might have found himself trapped when the victims walked in. He ducks into a closet, waits until he believes the women are asleep, then tries to slip out. Maxa's mom iis not asleep and sees him. The attack awakens Maxa's grandmother, and she is killed, too. Was the weapon identified? The scapular either went into the coffin, was pulled off during the attack and was lost/discarded in the aftermath.
That's the simplest, most straightforward explanation based on what we know so far. It's extremely unlikely that the perp would've burst into the house if he thought it was occupied. Unlesss you're dealiing with a psycho, perps don't like to attract attention.
ETA: Sorry, kemo. Looks like I was typing when you posted. I'm very slow on my nook.