hook_h5p_styles_alter fails to fire for Memory Game and Find the Hotspot

Problem/Motivation

We have been working on re-styling our H5P to match our site them

The custom module code is simple as shown below and it works fine for almostevery H5P content type that we have tried...

<my-module>_h5p_styles_alter(&$styles, $libraries, $mode) {
  $styles[] = (object) [
    // Path relative to drupal root
    'path' => \Drupal::service('extension.list.module')->getPath('custom_h5p_overrides') . '/css/custom-h5p-overrides.min.css','version' => '?ver=1'
  ];
}

We have successfully re-themed multiple H5P content types EXCEPT for these two:

1. Memory Game
2. Find the Hotspot

As far as we can see, for both these types, our overridden hook_h5p_styles_alter() simply does not fire.

It it possible for something to be 'missing' in these two content types to prevent the hook from firing?

Thanks all