Susan Sideropoulos played the role of Verena Koch at GZSZ until her serial death in 2011.
In the GZSZ anniversary episode, 30 Years of GZSZ (7510 on May 12, 2022), there is an overlap in the series universe when Jo Gerner hides from Bajan Linostrami at Leon in Engelshoop.
A scene (telephone call on a Baltic ferry; in episode 1 in series format) which Leon leads with John Bachmann (Felix von Jascheroff) is also shown at GZSZ (episode 7449).