Those are custom code examples, which I cannot provide or assist here.
However, I have to apologise as one above link is wrong.
This one is about to add a post type of YOAST to the relationships, not about putting related posts into their breadcrumb:
https://toolset.com/forums/topic/adding-parent-and-child-options-to-yoast-custom-post-type/
In the code shared here though,
https://toolset.com/forums/topic/2-custom-post-types-can-one-be-the-parent-of-the-other-and-display-breadcrumbs/#post-34778,
you would alter the code thereby changing employee
to the slug of your post type.
Then, in $parent = get_post_meta(get_the_ID(), '_wpcf_belongs_company_id', true);
you would have to manipulate _wpcf_belongs_company_id
and replace company
with the slug of the related post type (parent type).
That line will get the ID of the single Post (companies in this example) that is related to the current Post (employee in the example) (hence, is it’s parent).
Then, with array_splice($links, sizeof($links) - 1, 0, array(array('id' => $parent)));
it actually populates the Bradcrumbs using the Post ID of $parent
(the related post)
Since that plugin offers a filter for their breadcrumbs you can hook the above new data to that output with add_filter('wpseo_breadcrumb_links', 'your_custom_callback');
So the whole code is:
add_filter('wpseo_breadcrumb_links', 'your_custom_callback');
function your_custom_callback($links) {
if (get_post_type() == 'your-post-type-slug-of-child-type') {
$parent = get_post_meta(get_the_ID(), '_wpcf_belongs_your-post-type-slug-of-child-type_id', true);
array_splice($links, sizeof($links) - 1, 0, array(array('id' => $parent)));
}
return $links;
}
Let me know if you can proceed with this.
Please also remember that Types will be discontinued by end of 2018:
https://toolset.com/2017/11/types-plugin-is-moving-to-be-a-part-of-the-complete-toolset-package/