This is explained in the in-game tutorial. In case you turned it off:
Only Trump can enter the air vents and it's his only way to attack. When he does, a vent-banging audio cue will play, so headphones are recommended.
As soon as you hear the vent-banging sound, close the air vents using the control panel. Keep them closed until the vent-banging sound plays again. Once you hear it a second time, it’s safe to reopen the vents. Don't keep vents closed otherwise you will run out of oxygen.
For Epstein, he can be redirected using audio cues. Trump can also be lured away but your main priority should be Epstein. For example, if Epstein moves from Camera 11 to Camera 7, switch back to Camera 11 and play an audio cue. Epstein will respond to the sound and has a 85% chance return to that camera.
Epstein will not return to the same camera more than twice. Because of this limitation, you should develop a strategy that alternates which camera to lure him, rather than relying on a single location. For example, if Epstein moves to Camera 7, you can lure him to Camera 11. Once he returns to Camera 7, you can then lure him to Camera 9.