I have a watch that has the pressure tested sticker on it, but what if the caseback was opened? Sorry, but I need to learn more about our hobby and I have been nervous to ask questions so I don't sound as green as I am.
The stickers can't be trusted in my opinion. In fact there should or may be an unwritten rule, that if you open a caseback, you remove the sticker. However, the stickers are rare, especially the JWCII ones. In fact, it's going to hurt me to take it off, actually, I can't bring myself to do it. Rule out the window.