Hazel grabs the treasure chest as agreed. You both descend to the small crawlspace below the attic. You smash the remainder of the small circular window, and she throws the chest out to the sidewalk below.
You both drop down to the entrance, just in time for the roamer to break out of the basement, the door slamming on the wall beneath the staircase. It's clearly a ghoul looking for a fresh meal, and you're both on the menu. It rushes towards you both, leaving only the door on the left as an option for exit.

Thinking fast, you only have a few options:
attack the roamer,
run to the door on the left, or
show the roamer your book.