Custom Registration username_exists / email_exists

[Resolved] – It turns out the issue was a conflict with the Yoast SEO plugin. Yoast was re-sending the headers after the user was registered. So the errors were re-checked and the username_exists / email_exists showed up as duplicates. I was able to get around this by disabling Yoast just for the registration page with a code hack in the functions file.

If you run into this issue, here’s the code:

add_action('template_redirect','remove_wpseo');

function remove_wpseo(){
    if (is_page(5526)) {
        global $wpseo_front;
            if(defined($wpseo_front)){
                remove_action('wp_head',array($wpseo_front,'head'),1);
            }
            else {
              $wp_thing = WPSEO_Frontend::get_instance();
              remove_action('wp_head',array($wp_thing,'head'),1);
            }
    }
}