As I've already told you - repeatedly -, Timo, Worf knows one cannot see how a breen looks like by removing the helmet of his suit.
And he also knows about an 'urban legend' that anyone that manages to see a breen (which requires some doing but is not a priori impossible) is eliminated by the breen. An urban legend born, most likely, because actually seeing a breen is so difficult.
In other words, no contradictions. Deal with it - as opposed to being intentionally dense.