Install WG Tunnel on the Fire TV via ADBLink from your Mac. The APK is hosted here for convenience.
In ADBLink: Sideload APK → paste URL above → Install. Then open WG Tunnel on the Fire TV.
Generate a new WireGuard config for this Fire TV. The config is saved and accessible at a stable URL that WG Tunnel can import directly.
Copy the URL below, then in WG Tunnel on the Fire TV choose Import from URL.