I don"'t see the German article is relevant. It doesn't take a scientist to realize the human body has changing electrical parameters when the person is alive . That would seem obvious..
As far as I can see, the article does not rely on the fact that the person is alive. On the contrary, I find it hard to believe that 3.8kOhm @ 200VAC/50Hz from arm to arm was measured on a living person. That would be 70mA peak over the heart.
It is more like different means of conductance with different voltages, and different chemical processes in the ionic conductor at different voltages. So a Ohmian restance that is highly dependent on the voltage sounds similar to a varistor, which is an active component?