*After several hours (it takes an hour to retry tracking on a failure when you need to relocate the trail), the dog finds the trail again.*
"Assertion: Trail recovered. Action: Tracking..." the dog follows the trail.
*Heading back out of the square in a different direction, the trail takes the five of them all the way to the edge of the city and then out onto the meadows on the edge of the island, before it disappears at the edge.*
"Assertion: Trail ends here."
"Meh, probably hopped a flyer here."