Adapted M.A.C.O Covariant Shield - Placate not working?

The Adapted M.A.C.O. Covariant Shield Array has a chance that "any Attacker that hits you may become Placated for 1 sec". Unless the placate is working in an unusual way, I believe this is not functioning as intended. After allowing an NPC to shoot at me in the Japori patrol (advanced difficulty), I can see the placate trigger on the enemy's buff/debuff icon list (shows up as a solid white icon that says something like "subvert targeting system" or something like that). It also triggers Control Amplification, like a placate should. However, the enemy never loses target lock on me and continues to attack without pause. During this test, I did not fire my weapons at the enemy (to avoid breaking the placate just due to incoming damage).

I assume this would also apply to the Klingon Honor Guard Covariant Shield Array as well, but I was unable to test that specifically.