[Cerrado] The post type is now shown in the other language 'Invalid Post Type'

Background of the issue:
I am trying to remove some existing translations while viewing the website in German. The issue can be seen on this page: enlace oculto

Symptoms:
The post type is not visible when viewing the website in German. I expected to see the Content Block in the menu, but instead, I got no post type visible.

Questions:
Why is the post type not visible when viewing the website in German?
How can I ensure the Content Block appears in the menu for the German version of the site?