I would say it would depend on location, (if still talking about the idea) in the tower with the boss would stay hostile do to direct control but any where else turn docile do to nothing forcing them to do anything.
the only problem with this idea is how would the player know, which is the problem with any idea on xen, unless the player is told or given some good hints this would be more or less a hidden event.
EDIT: can’t stop thinking, so here are ideas to clue the player into the fact that the vorts are slaves.
first clue: the classic half life even(heavily modified) where the player runs into the vorts operating the thumper things, they are alone at the start and will not attack the player in fact they will run if shot at, after a bit 2 a grunts will enter the area and fire upon both the vorts and the player, once the a-grunts are dead a controller will enter and the vorts will turn hostile.
second clue: player runs into a lone vort that will say “Freeman wait” (or at least try to), if the player doesn’t kill the vort it will charge 30 armor.
third clue: player stumbles upon a group of dead vorts with an alien grunt in the area.