How do I open the cabinet?

Hint 1 of 5:

Brute force won't work.

Hint 2 of 5:

You'll need to find something to pry it open with.

Hint 3 of 5:

Do you remember what happened to Nico?

Hint 4 of 5:

Check out the floor to find a ...

Hint 5 of 5:

... poisoned dart.