I've found that putting a Thrall into any of its helper modes and then leaving the area, they immediately stop working. Coming back you have to cryo them and then set them to it again before they start. This is the same for logging off and back on. This has to be a bug, because otherwise they're more headache than they are worth.
Thrall
Thralls are infected human survivors corrupted by the Red Element in ARK: Lost Colony. These humanoid enemies wield weapons and coordinated tactics, often encountered in fortified strongholds and hostile encounters.
