This has been broken for a long time, I figured now that the Halloween Event is back they would have fixed it for the event but no, is this ever going to be fixed?
Unfortunately they don't care about this bug. Whats even funnier, many of the game designers and devs are so new they don't even know what a slasher IS. Sadly...
Mine doesn't even work properly. I died so many times last night because quick-knife simply didn't work.