@Death Star vs. "Moon"
Death Star wins. If the moon can go into hiding in plain sight, then sure, the moon might have a chance. But remember:
Isaac Clarke skewered the previously frozen moon with a bunch of markers. How much more damage could a bunch of capital-class lasers and 1 planet-busting laser that can recharge every 3 minutes deal on a single moon?
That said, if it were to go into hiding (hopefully as a planetary moon that the Death Star deems insignificant, because otherwise, there's no way you can't spot a large eyeball/pimple thing in space), it may be able to get a jump on manipulating the weak stormtroopers into doing its bidding and forcing the Death Star to basically kill itself. But the insanity only works on weak-willed people. Stronger people just hear and feel hallucinations, and that's not accounting the effects of the Force and how it could affect said hallucinations.
@Isaac vs. The Shadow & Daniel vs. Necromorphs
Daniel would die due to Marker-related insanity. He can't even look at the abominations in Brennenburg for minutes without killing his sanity. Might be mitigated a bit if he had Isaac's armor, but he has a weaker will than Isaac.
Isaac has become insane over time, so he might last as long as Daniel would in Brennenburg Castle if he didn't bring his Plasma Cutter and RIG with him. Oh, and also what Fniff said concerning Alexander.