Hey Oliver!
Thank you for reporting all of this. In your other threads you reported some bugs and we are working on those closely! Here, however, the numerous text domains you show in your screenshot do not come from one file.
They are separate domains for separate pieces of software, and so this separation of strings is by design.
I will log the issues of the strings not translating that you highlighted though – thank you for highlighting these!
I will close this thread – please keep all followups in the following thread: theeventscalendar.com/support/forums/topic/issues-with-german-translations-in-tec-3-12-6/
That will help us keep things organized here.
Cheers!
George