It is weird how the plugin does this but try this:

Save the list of things on the page via custom state

Set the latitudes and longitudes with the same search (make sure it is sorted exactly the same). Also set the Unique name to something predictable like marker-

Then when the user clicks the marker it triggers the event:

So you basically take the marker # clicked, it finds the Thing in the custom state list with the same # position and sends that to the next page. The next page has the same datatype as the custom state list.