I've completed the vault 64 quest but I've still got an exclamation mark outside of the vault. The quest journal says I never completed the "find the secrets of vault 64" part. I'm wondering if I've missed something or is this just a bug?
The quest "Scanning the Wasteland" requires you to go back in their. If you haven't completed the quest, it may be the reason why the exclamation mark is still there.