Hey! Happy to hear you enjoy my stuff~
Regarding The Factory: If the characters enter through the sewers, then they have to go through the corpse disposal. But don't get too hung up on all the lines, it's free for interpretation how to roam the factory grounds. Other options to enter the factory grounds are the gates, or cut a hole somewhere in the fence. I haven't gone into detail for the latter option, but it should be very dangerous and should raise the alarm as well!