Adding javascript to module and access drupalSettings without jQuery
You can try to set a weight on the js file:

  js:
    js/mautic_drupal_tracking_code.js: { weight: -18 }


There is a core issue, that the dependencies don't get the correct priority. The weight is a workaround for this:

Replace custom weights with dependencies in library declarations

If you can't get drupalSettingsLoader.js running in the correct order, you can for testing purpose put the code to load the json array at the top of your custom js:

(function () {

  'use strict';

  var settingsElement = document.querySelector('head &gt; script[type="application/json"][data-drupal-selector="drupal-settings-json"], body &gt; script[type="application/json"][data-drupal-selector="drupal-settings-json"]');

  window.drupalSettings = {};

  if (settingsElement !== null) {
    window.drupalSettings = JSON.parse(settingsElement.textContent);
  }
})();