Never seen anything like that as far as I can recall on mine. Might have been something there when it came out of the box. However, I just pulled everything off without taking much notice. I would suggest that with the hole covered barometric pressure readings would be compromised.
I'm not sure what that is where your stick once was, but it was my understanding the barometer sensor was under the hole centered on the bottom just left off the "Taiwan" stamp in your pictures.
Replacement has arrived, I was right, but looks like they changed the sticker. My origional that has issues had a silver sticker that came off whilst on holiday in very warm conditions....