The two Laws in question are: Thou Shall Not Invade the Mind of Another and Thou Shall Not Enthrall Another.
These are two very separate instances, though they can run together. Psychomancy can result in thralls, yes, but that is not the only magic that can create a thrall. Addictions, specific hexes and spells, potions- all these things can be used to enthrall a person without psychomancy.
The most powerful love potions, in their truest form, are an example. To make a person fall in love is impossible- but it is possible to make someone fall into obsession or infatuation which can then be used to make them do things they would normally disagree to.