Hi @masterhealerwp,
Since you have no answer to your questions for so long time and I feel like this plugin has been left with no support at all recently (including for XSS vulnerabilities), I would suggest that you switch to this plugin:
https://www.ads-software.com/plugins/wp-date-and-time-shortcode/
In general you can find the answer to your question for any plugin in the following FAQ answer listed in the WP Date and Time Shortcode:
The shortcode doesn’t work in all places e.g. page/post title, footer, menus, etc.?
WordPress applies the shortcodes in post’s and page’s content by default. If your theme does not apply shortcodes in other places automatically you may need to add additional code to your child theme’s functions.php to hook into those functions where you need to see the shortcodes applied.
For example:
// For the titles.
add_filter(‘wp_title’, ‘do_shortcode’, 10);
add_filter(‘the_title’, ‘do_shortcode’, 10);
// For the menu.
add_filter(‘walker_nav_menu_start_el’, ‘do_shortcode’, 10);
etc.
If you have a SEO plugin that does not support shortcodes in SEO meta tags you can still use their hooks (filters) to apply shortcodes before displaying. We have created plugins for the purpose in the past Do Shortcodes for Yoast SEO and Do Shortcodes for RankMath SEO older versions but I am not sure if they still work and that the hooks are the same. We also had Do Shortcodes for All in One SEO Pack but they apply shortcodes by default now and we deleted our old plugin (for the old version). However you can see the principles of their work in their code.
Eventually for the slug you may use the wp_unique_post_slug filter.
