Find the foreman quest bugged

 I cant complete Find The Foreman quest because i accidently entered the cave too fast and past the blockage without destroying it. And now i cant destroy the blockage because it regeneretes health and since i cant destroy quest objective doesnt spawn. It has been 2 days and i cant advance in story line.

when i first i started this game in cataclysm i could contact with blizz employees who would fix my problem in seconds. now they dont even give me a chance to online chat with blizz empolyees. when i type my problem they direct me to topic something unrelevent my issue. And they cant even solve simple bug they are aware of since launch