The Vault is an isolated dimension which has no bearings on the real world which is why Atheon, The Templar and Gorgons are not seen anywhere but inside of it. If they could succeed in transferring their existence into the physics of our universe we would cease to exist. Once you travel into this dimension however you can be erased from time (as Kabr and his team were) which is why they are/should be referenced as they have/had bearings in reality.