Only one Tab in WPUsers-Profile translated

Hi there,
having spent days with this by now – not successful – I now ask you and hope you can help me.

For my directory I am using the UsersWP-Plugin. In the user’s profile there are three tabs shown:
Listings
Favorits
Comments

I have uploaded the completely translated German po-File on the server,
at
… /wp-content/languages/plugins
(see Screenshot1)

as well as

… /wp-content/plugins/userswp/languages.
(see Screenshot2)

However, only one of the tabs in translated into German (comments = Bewertungen). Listings and Favorites are still in English, just like some other strings which are definitely translated in the file.
(see Screenshot3)
Is there any other po-file to translate the plugin or any other location on the server where I should save this to?

Or is there a way how I can from the frontend find out where exactly the po-file for a certain string is located on the server?

Happy Easter and looking forward to hearing from you – maybe after Easter, which would also be okay.
Many thanks in advance
Birgit