You can get any positions of any object, they're not stored locally.
To convert a position array you can use the mapGridPosition command.
_pos = mapGridPosition player;
hint format ["Map position: %1", _pos];
"Player" is local to each client. If you want to find the location of another object, just change player to whatever the name of the object you're trying to find is.
_pos = getPos player;
// _pos is now an array with [X,Y,Z] information.
_mapPos = mapGridPosition _pos;
hint format ["Map position: %1", _mapPos];
The grid position on the map is just a visual for players to make it easier to identify for themselves and others where they are. It's not what the engine uses for positions, and thus needs to be converted.