This mod adds a henchmen ability named Spotter which allows NPC teammates to mark guards and security cameras during stealth gameplay.
Bots can stealth too, if you tell them how.
Control of a NPC teammate is handled by , hold Stop AI key for 0.5 sec to wake him up:
Note that a masked bot can reply to the pager operator, you just have to put a waypoint on the dead guard and give the order.