Dreghood slaves in Hellfire and Zangarmarsh don't run after their slavers are dead

[BatuKhan]

As title says. When you kill the demons in Hellfire, and when you kill the Naga in Zangarmarsh, the Dreghood are supposed to turn yellow, run off and despawn. In Hellfire they stop attacking you at least, but in Zangarmarsh they remain aggroed and you have to run or kill them.