I mean, you can still see them when shooting an obscure target. Like shooting through shrubs, or grenade smoke residue.
I don’t think pinging should work. It would make the threat sensor redundant.
I get that, but in the case of the Shroud Screen, it’s entire thing is complete concealment, so hit-markers kind of negate that in a way.
I agree that Marking shouldn’t reveal what is inside the Shroud Screen. Maybe have it mark the screen itself, indicating that one has been deployed. On the other hand, if a Threat Sensor is already revealing an enemy or enemies inside it, I don’t see why Marking shouldn’t work in that instance.