on the other hand - I had contractors install our Nanoleaf recessed light cans (thread over matter) in our new house. In all the hubbub, I forgot to make sure to save the light cans boxes that had the QR codes inside. I found around half the QR code stickers, but I lost the other half. The light cans also have the QR codes printed on the top, but we have nailed-down attic flooring that covers them completely. So I'm basically just praying that Nanoleaf's CS can give me the pairing codes based on my order number, haha.
Oof, yes that's certainly a way QR codes can go wrong. Ideally manufacturers print the QR code on the device such that it lasts the device's lifetime.
It would be nice if technical users (installers) could reset the certificates or keys too. Besides losing the QR code, secondhand owners also want some assurances.
Usually these LED puck lights are only held in place with little spring-loaded arms that grip the back side of the drywall, and all you need to do to remove them is tug on them a bit and they'll come out. The light is connected to the electrical junction box with a short low voltage cable with a plug on it, and the LED driver and line voltage connections are all inside this junction box.
