We should know for sure very soon as to whether the mask is just a prelim. On the back of the bag should have the date the bag was printed, if the date is recent then the mask is likely intentionally their. If the date is old, then it was probably a prelim that got passed onto the bag when they still planned for it to be a mask.
As for the Vahi resemblance, I do see the resemblance in the lower half of the mask. Specifically the circular mouth and the triangular area near the nose and the side of the mouth.
Either way, part of me cant see this mask being an early prelim for the Mask Of Creation, given we have seen concept art of the Mask Of Creation and it never seemed to be anything like this mask. This mask seems pretty finalised to the extent where it was printed on a bag and used as a display on pretty much finalised sets. Having this mask scrapped and replaced with an entirely different detailed mask seems unlikely to me. So going with the theory it is actually going to turn out to be the Mask Of Time.
-coughs- I was the one who linked it on Brickset
Though for some odd reason they credited someone else despite my comment being in the comments with the link :L
You can see a full gallery of image here
Gallery is someone else's btw, just linked it to Brickset