I’ll try to explain myself a bit better.
None of the coordinates of the places have changed just because you have changed the default location, only the fake addresses have changed.
Only the coordinates of the default location were changed, but that location itself is not shown on the map; only places/listings are.
If you want the dummy places to change coordinates, you have to go to each of these places, click SET ON MAP to update the coordinates.
I have done that for one, and you can see the result of that on your homepage
Nobody will now be able to add any places outside your new default location, but if you want the places coordinates to change, you have to do that yourself.
There is no marker for the home page or for a location. There are only markers for listings, and as soon you changed all the coordinates one by one, they will not move on the map. So your map will keep displaying listings you added with “old” coordinates.