I believe that the latitude, longitude, and region of a data center (the location information displayed by the ICP Dashboard) is controlled exclusively via NNS proposals, as I indicated in a different thread.
You seem to be asking if there is (ongoing) validation performed that the locations of nodes and data centers specified in executed NNS proposals are accurate. That would be outside of my area, so I’m not aware if something like that is being done or if there are plans to do so in the future.
As far as the latitude and longitude goes, I recall that in the past this has sometimes been an approximate location, for example coordinates within the same city. For node provider remuneration, that is fine, but I understand your point about accurately differentiating data centers by using the geolocation of its nodes for purposes of determining subnet decentralization.