Think your unescaped “&” in the URL was triggering “run in background” - see e.g. https://unix.stackexchange.com/questions/86247/what-does-ampersand-mean-at-the-end-of-a-shell-script-line
So indeed, curl will run, but just not with the URL you thought, and you’ll get all the odd side-effects.
I’ve found using curl from shell / command line is good for basic testing. It’s slightly involved if you want to download documents. For that you have to trap the http header with the -I or --head option, then head off to the address returned. This is somewhere in amazon’s domain. IIRC you may get another redirect once there? Anyway it works fine in our code but sometimes gave me problems when doing this from the command line with curl.