Yes, with silent assassin on you can kill a guard without having to answer his pager. However, this only applies if the guard hasn’t spotted you yet. You can download silent assassin on the paydaymods website and you can use it by dropping the file in your BLT payday gamefiles. (You can also download blt on that website and there are many tutorials on how to do this online.) However, even if the game might not mark you as a cheater I wouldn’t recommend you to use it because it takes away one of the most crucial parts of stealth: limited killings. In normal stealth, you can only answer 4 pagers, which limits your killings but with silent assassin you can kill EVERY SINGLE GUARD on a map! This makes stealth very easy and you can easily beat shadow raid on death sentence in under 7 minutes with this mod enabled (with all loot!).