Bullshit Meter: Direct Köln - London trains will depart Gleis 5 at Köln Hbf
A news report in the Kölner Stadt-Anzeiger reckons direct trains to London will depart from Köln Hbf Gleis 5 (Platform 5).
I have analysed this in much more depth in this separate article, but it strikes me that while the idea has some merit, it is still a hell of a long way from being achievable.