So let's say, theoretically*, that this bug was still occurring for one unlucky player*. How would that unlucky player* go about completing this quest? Filing bug reports does not get a response, and the categories for which you can file tickets are extremely limited, and there is no real customer support. Is this player* simply screwed?
*not theoretical, and that player is me
The bug at the time was a result of a mistake made when trying to add While Guthix Sleep to the Christmas event map. The door kept was not the While Guthix Sleep door. We fixed it temporarily during the event. Finally we removed Christmas alltogether, reverting the map square to before the bug. In other words, it was broken for everyone, and now it is fixed for everyone. The clue to identify if it is the same bug is that the location should be called "Cell gate" rather than "Cell door".
I think you may have a different problem. Could it be you're on a Free world?