The rear sprayer inside the third brake light broke off on my 2011 a few years ago. I didn't realize there was a screw from the inside; I took out the outside screws and yanked the light out, There was an insert in the light, which the inside screw went into, That stayed on the screw and came out of the light. I don't remember well, but it wasn't so difficult to get out and wouldn't have pulled so hard to risk breaking it (I figured the screws were already out, it must just be on a post or something...).
To put it back, I just pushed it in as far as it would go to; I don't think it went all the way back in at first (the light seemed a bit pushed out in the middle), but think the pressure from the outside screws worked it back in.
For my issue, I silicone glued the sprayer back in, it is still fine years later.