That moogle actually appears in every zone in the same map location until you target him. You can see him floating over the water in Windurst Waters [S] if you look and he appears in Port/Lower/Upper Jeuno. They already tried to "fix" it and banned people for using him to change jobs (which you can still do, by the way).

There's also a similar invisible wall to what you're describing in Northern Sandy by the mog house.