Daily Quest BUG, "Troll Patrol: The Alchemist's Apprentice"

Greetings. The daily quest given by Alchemist Finklestein in Zul'Drak, called: "Troll Patrol: The Alchemist's Apprentice", looks like it might be bugged.

You're supposed to mix a series of items in a cauldron, the quest begins, Finklestein shouts the first ingredient, it's all timed, and after you burn that said 1st ingredient, nothing happens. He is supposed to keep gradually shouting for the next and the next ingredient until a Truth Serum is complete. However, after the 1st ingredient, quest stucks. Tried relogging, deleted cache, nothing. Any hints?