Sam was surrounded by the black smoke as he used the shadow mode and bypassed the three ladies. The target is in the middle of all three of them and he definitely didn't think that Sam would just jump at him like that.
He is just a Pre-transcendent stage cultivator and he knew about the name Robin Hood who is the person that burned a Transcendent stage cultivator alive.
He wanted more people to present in the room so that he can use them as meat shields if he has to.
He knew that since this Robin hood, can enter his bedroom without anyone in the street full of guards noticing, he has to be careful. As for being a witness, he is just bluffing to buy some time to make sense of the situation.
This trick would have worked on normal people. A guy with confidence and calm will seem like a difficult target.
