Final report. My girlfriend landed, but the Tile app did not pick up her location until just before I saw her appear around a corner. All the app did at that point was flash "Connecting" on the screen but as she got closer, the app reported the bag's location as the street address for the airport. This experience meshes with Tile's official spec that it works at a radius of 400 feet so I remain satisfied with the results of my test.

Now, I'm hoping I won't need Tile's help next month to find my bag, but I believe I have enough confidence in the way it works that I can hope for some assistance should my airline lose my golf bag.