If you use the VGPS function on Project-GC (which is a paid function on Project-GC), then one person can update the corrected coordinates for the caches and put them in a VGPS list and share the coordinates. After that, the people that the list is shared with can choose to update their coordinates for the caches in the list from the VGPS list, which will set the corrected coordinates for these caches in their accounts.