I can't find the term in "transit passenger" in any lounge access rule.
I don't know where the OP got the text from but the English version of the
press release does not mention "transit passengers".
Lufthansa First and Business-Class passengers as well as customers with Hon Circle, Senator or frequent traveller status will enjoy a unique perspective at the end of March at Frankfurt airport: It comes on stream with the opening of the new Tower Lounge in Departures area A above gate 65.