It would have to be something like an AirTag or Tile, otherwise it would be pointless?
The only reason these are useful is because of the vast amount of phones that will report the location of the bluetooth tracker. A $10 chinese version wouldn’t work so well.
Since it was Dutch news and Dutch ship - I'm betting they used ~€5 Bluetooth tracker available in Action stores.
Not sure how different it works from Apple/Samsung trackers. But my Motorola Android phone can set it up, and phones out and about are reporting where it is.
The only reason these are useful is because of the vast amount of phones that will report the location of the bluetooth tracker. A $10 chinese version wouldn’t work so well.