[Scool's out forever] bug?

Hello everyone, I write here hoping this is the right place to do so.

For some time now I've been trying to complete the instance achivement "school's out forever" as it is the only achive I'm missing to get the mount.
The problem is, that it seems to have buged out for me. Done it 3 or 4 times now I think and still I dont get it completed (everyone else in the group gets it tho...every time, so it shouldnt be that we fail it as far as I can see.)

I made a GM ticket hoping they could help me somehow. When I finaly got an answer more then 24h later, all they said was that the GMs couldnt help with that kinda problems and that I had to report a bug.
Reported it many days ago now, still doesnt seem to be working.

So, how does this work? Do I get a PM or mail of sorts when/if the problem/bug gets sorted, or do I have to run Scholo every day to see if it's been fixed?

Hope it can be solved in not too long, I dont usualy care about achivements... but as I actualy bothered doing this one it would be nice to get it. :)

/Sharoc