Head to the marked location then deploy Ikaros to scout the area once you see the prompt. Fly towards the abandoned house and spot all five hostiles.
Approach the location from the southern side and sneak behind the house. This gives you access to the back door where you can take out any sleeping guards and take out the lookouts from behind with ease. After taking out all targets, a cutscene will take place.
During this scene, Elpenor will give you another job. You can ask details about the shroud that he wants you to recover before agreeing. Nevertheless, you have no choice but to accept the next mission anyway and the current mission will be completed.