Hey everyone, first off loving the game but I've run into a little snafoo,

 

I got the key from the crucible knights earlier to get into herritage hill, ran around a bit in there (saved the girl, killed some ghosts) but didnt have the quest (or information) to go past the stone gate.

 

Anyway long story short now that I do have the quest the justicars wont let me past the gate, and I cant open the door myself (despite getting the key from waela before and having gone into the area before) .. 

 

What should I do, is this bugged? 

bump for justice, I'm still stuck