I have been trying the sniper approach from the roof of the mansion in the Dartmoor level but facing an issue while trying to achieve a Silent Assassin rating. Whenever I snipe Alexa from the mansion’s roof the Undertaker always sees Alexa’s body in the grave and immediately the game triggers a "Body Found’ message which kills the SA rating.
I have made a video of my play-through of this level on Master Difficulty and here is the link to it:
From the above video of my game-play you can see I even took out the personal bodyguard of Alexa Carlisle beforehand because otherwise he also follows her to the graveyard. Negating him decreases the chance of Alexa’s body being found (but alas, the Undertaker spots the body each time anyways). I have noticed however that if the personal bodyguard is not taken out before Alexa visits the grave then sometimes after you take the sniper shot to eliminate Alexa when she stands near the open grave a “Bullet Impact Noticed” alert pops up. That particular alert can also more often than not pop up when you are shooting the bird nests on the trees in the graveyard from the roof. I don’t however think that alert ruins the SA Rating in anyway. I usually only shoot the nests when the Undertaker walks away from the open grave area. He can also notice the bullet impact in the trees. Before I take the shot to eliminate Alexa I first shoot the foreground area to distract the Undertaker. When he turns around I shoot Alexa. If you see closely the Undertaker actually runs away from the grave after I shoot Alexa but after a few minutes I think he walks back to that area and that’s when he looks into the grave and spots Alexa’s body.
So, is there any way to get a Silent Assassin Rating after shooting Alexa into the grave? Or is this a bug that prevents you to do so because the no matter what the Undertaker will end up noticing her body and trigger the “Body Found” alert.