There are a few ways to isolate overlapping nodes with Voyager.

One example is provided below, where the first Network program outputs the node table defining rounded values of X and Y with a certain tolerance (imposed in the script).

The second Matrix program isolate only those node records that are overlapping (accordingly to the defined tolerance for X and Y decimals).

communities.bentley.com/.../network_5F00_node_5F00_duplicates.zip