“...but without the international volunteer cave divers that were flown in (reluctantly by many of the Thais leading the mission)...”
I recently started watching a youtube channel called Adventures with Purpose. A small group of divers that search bodies of water with their fancy fish finders (including side-scan sonar) looking for missing persons in their vehicles. Some are a few days old, some are 30-years old.
Most of the police have been pretty good, but there are some that don’t want their intrusions at all. In the last couple of years they have found something like 20 people. Some in only a few hours! Lots of these small towns don’t have the resources, but some of the towns/cities you sure wonder what the police were doing.
Adventures with Purpose are good people.