Can't find this Windows Spotlight wallpaper anywhere

I saw this wallpaper on my Windows Spotlight lockscreen around July 8th and I've been trying to track it down ever since. Checked the usual Windows Spotlight cache folders, looked through online archives, even went down a few rabbit holes on image search—still nothing.

It's a really nice one and I wanted to save it to use as a permanent wallpaper, but it seems to have vanished into thin air.

Anyone recognize this or know where I can find the original file?