My group played this chapter with 4 players and managed an easy win for the heroes - the traitor didn't manage to kill anyone.
The problem was (and this is happening more often than not) the traitor's tome & secrets of survival are daunting, particularly for casual gamers. It's always a lot of information and there's usually something in there that only makes sense when the opposing team does something (which wouldn't be a problem if that was made clear in the books - instead, players are worried they've missed something or forgotten a general rule).
In this haunt, the traitor didn't understand all of her options and didn't bring in any more cultists, so after the initial batch were dispatched, she was just trying to chip away at the heroes while we searched for who the cult leader was.
All that aside, we still love this game - the overall experience has been great so far. But when the haunt happens, the gameplay slams to a halt and everyone spends the next 20 minutes reading and re-reading their books with confused looks on their faces.
Does the traitor move either of the inhabitants?
Nope, just the small monster "cultists".
One of the inhabitants is nothing to do with the traitor and the other one is incognito, so if the traitor started moving them it would out them as the leader.