[Risolto] Need to translate the Ninja Tables Header - I created the translated version - but cannot find the t...

Background of the issue:
I need to translate the Ninja Tables Header. I created the translated version but cannot find the table on the translation page. I have created the Ninja table shortcut for the Slovak version, example: [ninja_tables id="25988827"]. Also, created the English version: [ninja_tables id="25988829"].

Symptoms:
I was not able to find that shortcut on the page or via the strings. I suppose some setup is missing.

Questions:
Why can't I find the Ninja Tables shortcut on the translation page?
Is there a specific setup required to make the Ninja Tables Header translatable?