It looks like the switch can be wired normally open or normally closed.
If you have a DMM put it on continuity and put one lead on the bottom tab and the other on one of the other 2.
For use as an outhole switch you should only have continuity when the switch is activated. If you have continuity until the switch is activated you have it on the wrong one of the 2.
Yes the green wire will go to the bottom most tab regardless.