Building a Manufacturing Capital is something that can be done by more than one race, hence that is not a bug. (I love giving the minor races the Advanced Computing tech right when I meet them, it makes them like me and later I take over their planet and remove other buildings to replace with research buildings, Super Tech Planet!)
Building a galactic wonder such as the Tri-Quan building is one of a kind period, no other races can build it after one does so that is a bug, and I wonder what happens if Its a trade good... Could you use it for trade more than once? I think I'd just remove it from the build que personally because it seems a bit cheesy to me, but hey, you play the game the way you want to.