Hmmm, I wonder if the door would have guards. It might be a bit too obvious a way to signal that there's something precious in a room where they might not want to call attention to. Or... our dear Master of Commerce might not even imagine someone would try to break in. So a locked door, very likely, but guards, not necessarily.

[In which case...]

I am not inconspicuous in those clothes. It's best for me to go mingle, and you can contact me with the crystal if anything happens. Remember other people might be listening on it.