Everyone on the floor has their own QR, their own numbers and their own screen
Floor
A five-star review of the venue is no use to anybody. A five-star one where the customer names who served them changes two things: that person can be recognised, and you can know who makes people come back.
Everyone on the floor has their own QR code and their own screen, reached by a private link, where they see what they have generated. It installs on the phone like an app.
The management consequence arrives afterwards and it is the one that matters: when you know which person on your team makes people come back, you know who you cannot afford to lose.