It does, because it is in itself bugged (as has been reported in other threads). The Dreamer only eats that drug herb (Drudanae?) from the Large Orange, and doesn't accept any other (even when you find the same herb in the marshes). Thus, I am obliged to let him consume the herb, and when I give back the orange, the fight with Griff happens.

Anyhow the quest was supposed to advance with Zaleskar (the undead trader) as well, and it did not.