Changed sub-site to its own domain trigger 302 redirects for all page links

Your wp-config.php indicates that you’ve set up a subdirectory installation, but you want to be able to use different domain names for the sites. To do that, I believe you’ll need a plugin of some sort.

A quick search indicates that WordPress MU Domain Mapping may do what you need. Be sure to read the installation instructions carefully — it looks somewhat more involved than the usual “put the plugin in wp-content/plugins and activate”.

Caveat: I have a fair amount of experience in WordPress Multisite subdirectory installations, but my WPMS subdomain knowledge is pretty thin. If I’ve made an error, please correct me.