Use Watchers as a cooperativc test, each Watcher adds +1 dice to assensing test (As a sole watche assenses shit if he stumps into it, but due to their psychic link with you, it is like to have more eyes to see the scene).
The place has 3 Background count, so it is -3 modifier for your assensing.
Adjust the pools, if you haveto roll more dices, roll them and add it to the post, if you need to roll less dices, tel me how much, I will extract the rolls in your link..