Ha Long Bay was discovered by an AI, but when they settled an outpost on that territory I got a grievance against them because they settled the nat wonder I discovered! Sorry, but I missed getting a screen shot of that cos I already used the grievance. 

Secondly, I am playing as Babylonians in ancient era, the gold star for science fame points is 15 techs, but there are only 12 ancient techs, so as far as I can see that makes the gold star impossible to get. 

If you share maps with an AI when they discover a wonder you both count as having discovered it. (same if you discover something)

Babylon is a science culture, it can keep researching into the next era.