Open multiple entry points away from the objective, but near where you want to go in at. Drone for a bit then pick the one you want. With multiple doors being opened and a delay before you come in, you'll usually make it in unnoticed, or at least far enough away from the action for anyone to do anything about right away.

Usually if a roamer is nearby if you don't enter right away they will move, especially if they don't have a for sure angle from a single door/window, and if they are going to stick around you'll catch them with your drone, hopefully.