Why doesn't the Marker protect smart people?

Why doesn't the Marker tell the Necromorphs to not harm anyone that's able to comprehend it? Since they'll eventually make more Markers, heck why don't the Brethren Moons tell the Markers to tell the Hivemind for the Necromorphs to buzz off!

...mainly cause they spook me :(

Also the image is unrelated, I just thought it looked nice. If you know who the og artist is just say it, I'll credit them then