Raspberry Pi 5 teams up with Radeon GPU to run Doom Eternal with RTX on at 4K — the combo also tackles Crysis Remastered, Red Dead Redemption 2, and Forza Horizon 4

It's an AMD GPU, so how does it have anything to do with RTX, which is a marketing name for a bundle of Nvidia technologies including the CUDA compute framework, an AI framework, and of course a ray tracing API (which games generally don't touch, because that would limit their ray tracing implementation only to Nvidia GPUs)?