Hi...welcome back and thanks for posting a reply
I understood that the thumbturn (as shown in the image) is on the inside, that's what I'd expect on a bathroom door. However, I don't know why you'd have a keyturn/key hole on the outside. You wouldn't need to lock a bathroom door unless you're in it! In the case of locking handles like the one in the image, there would usually just be an emergency release hole/plunger on the outside. I've never seen a bathroom door with a lock that can be locked with a key from the outside (apart from old lever lock doors which by design have keyholes on both sides).
Cheers...