I must admit I am not sure it is the right forum, but I think it could fit. (be encouraged to do more wonderful riddles like you did in the past)
It appears like some kind of bug, but its even possible it is intended.
At least I had a good laugh over myself and for me, it was one of the best game experiences at all to figure it out.
OK, I don't want to spoil it for you and I am in hope you have some fun with it too.
And please if you know already the solution don't spoil it here (foremost if someone else told you the "workaround").
If you know the solution, you could give a small hint, if you want to show you know the solution.
My hint: it is in the Quest AtDQ and due to my play style it was very hard to figure it out for me, because it rarely appeared in my groups. (and no, on ddo wiki is yet no hint)
Edit:I just don't want to bump it up, because I see there is not much interest.
But it gives me another idea when I see this, so it was maybe good for something.
I tested more around this issue and figured out, my theory was not correct even when 100 tests seemed to confirm it, the workaround is even more simple and it is surprising that so many player's including myself are not able to see it much faster.
Anyway the bug is not really harmful and its maybe not to bad if it remains as it is.
It's just a good example to be blind to something quite simple.
And I doubt anyway that it would be fixed because of the very low priority of old content.