I misunderstood you, then -- what you described I wouldn't call social manipulation. It's just figuring out the individual's pain and pleasure points and then applying the proper amount of pressure to them -- nothing social about that.

Whether I can imagine an AI having superpower-level psychological manipulation abilities (but NOT superintelligent at the same time), I'm not sure. On the one hand, you could probably call it a narrow AI, on the other hand it might be that the superpowered ability to manipulate humans does require enough AGI-nature so that the AI is essentially an AGI.