I've followed the walkthrough exactly, and Josh isn't where the walkthrough claims he is at. I see Riley & Chloe, but the walkthrough says to talk to Josh first, and he isn't there. So, from where it says Josh should be, I try all directions and he is nowhere, but Chloe and Riley are right around the corner.
EDIT: John also isn't in the utility room after killing Riley. Emily also isn't anywhere at all, so just skip those 3 people and you'll finish the game.
Not sure if they were supposed to be there then were omitted or if the walkthrough is just wrong, but regardless, hopefully this will save some frustrations. lol