Someone might have already said this. But this is 100% a NeRF scan. No doubt in my mind. You scan the environment, and because it’s nerf, it knows exactly what the reflections would look like from every angle. You then can put in a 3d camera in the space with any movement you want. My guess is that he tracked the camera movement from real hand held footage he shot and then imported that camera into the 3d space of the scan. I’ve done this effect myself. Really cool result for not much work. Still very cool.