Yes the issue here is that the URL you’ve provided actually returns an HTML body (as well as the redirect header) and that the redirect is to a relative URL, not an absolute one including the protocol prefix. Annoyingly, the fetcher is pretty finicky about this.
Two things to try:
- change the redirect to include the
http: prefix on the cdn relative link
OR
- avoid the redirect altogether (which is obviously not ideal, as you lose the benefit of the CDN)
I have a hunch the first option will work, but if not, try the second. In both cases though, bear in mind the 7 day cache on the cards crawler, so things may not resolve straight away.