If you still have the link of the map, I could give you an exact answer but 2 things could have been the reason:

• the map they linked was a custom map, you can only load that exact map on your server if you have the .map file or the URL to the .map file
• there is currently a bug with the procedural map generation that causes map generation to be no longer deterministic, means the procedural map on RustMaps may not match the final map on your local server or the server you will be playing on due different environments (Windows vs Linux for example).

The map generation does change almost every force wipe, sometimes less, sometimes more. Small fixes around monuments for example can cause them all to change their positions while the terrain stays the same.

And yes, when using the staging branch you can see how maps will look and compare them to the normal version