One of your iframes is loading "https://onedrive.live.com/embed..." . If I open this directly in another tab I get redirected to https://login.live.com, looks like I have an account there but I don't know my password. If I open this directly in an incognito tab I get redirected to the error "This item won't load right now". But if I load https://sites.google.com/view/sharet...ividual-result in an incognito tab it does work. I have a bunch of cookies for onedrive.live.com.
So I think it's not working for me because I have an account at onedrive.live.com (which they detect via the cookie) but I'm not logged in.