4k video only downloading from icloud as 720p (I already tried "more download options")

I have a 32 gig, 1.5 hour long, 4k video that I am trying to download from my iCloud. I have tried every single download option on icloud[.]com/photos (download, more download -> unmodified, highest res, most compatible) but no matter what I do, the downloaded result is a 2.3 gig 720p video. The video info on iCloud even states 4K, 3840x2160, 31.4GB, H.264. I tried downloading on both my iPhone and Windows computer, with the same result of only 720p.

Everywhere I look says "click the 'more download' option" but I have already tried that and it doesn't work. Any help here would be greatly appreciated.