Where was Prospect filmed?
2018 film by Zeek Earl and Chris Caldwell
Wikidata records no filming location for Prospect (2018) at all, not a place, not even a country. There is nothing to pin, and this page says so rather than guessing.
Why there is no pin
Its Wikipedia article also says it was filmed in Washington, without naming a place, so it is not on the map.
Filming locations that are mapped there: United States