The box says there are 22 cards in the exhibit deck, whcih I have, so no cards missing. But last time playing the expansion came across an encounter in the Inner Sanctum of the Silver Twilight Lodge that refered to taking the Triune Mask card from the eshibit deck, but that card doesn't exist. Just wondering if there was any official ruling on what card the Triune mask is supposed to be? (we used the Mask of the Three Fates just because there was the Tri = three connection).

You got it right. The Exhibit Item was renamed before printing, but other cards referring to it didn't get updated.

Thanks for the reply. Good to know we did it right.