This "editor of major German newspaper" is also a fascist wannabe politician, associated with far-right Pegida and it's predecessors. It's a little convenient that he realised he'd been working for the CIA this whole time, about the same time he realised his potential far-right voters gobbled up any old bullshit that validated their racism and feelings of victimhood.

He wrote a book about his CIA claims, but the title given in the linked article is the German version, the English translation is called "Presstitiutes". The fact they use the wrong title makes me think they probably didn't read it.

I can't find it in libgen which means it was never released as an ebook. From the reviews I read, nobody could identify an actual single story of his which the CIA contributed on. It's a little bit weird that, having apparently taken direction from the CIA for so long, he never actually identified a single instance of their direction, kind of sets off my bullshit meter.

Then I looked at his public appearances during his final years, 100% of which were on russian state controlled media, and I realised that even if his claims were true, he clearly doesn't care much about governments controlling the mainstream media - after all, he had no problem with Russia today who are far more compromised than his Frankfurter zeitung (which has less than one quarter the circulation of Bild).

Ultimately I find the sourcing here to be bullshit for the reasons above. He's a crackpot fascist conspiracy theorist with strong ties to the Russian state media, and none of his claims are sufficiently grounded in reality to be critically examined for truthfulness.