Chapter 4, Challenge 6..

Hey guys, I have such a problem with the challenge! Each time I do that specific kill on Bob. Lynda’s bitch ass is always coming downstairs. I close the door because Bob isn’t closing the door when he goes down to get the damn beer! Can anybody please help me or do I have to just restart the whole chapter again or is this chapter bugged. I wish GUN/ILLFONIC FIXED THEIR GAME OR SKMETHING MAN.