Isn't much of the noise in VLOG due to less aggressive noise removal, not necessarily that the camera does worse in that mode?
Lumix cameras have a waveform monitor, and I always use this to set exposure with V-Log, from way back when I first had a S1H. The terms over-exposure or ETTR don't mean much with log video, and a good practice is to learn to ignore any exposure meter readings. I expose so the brightest part of the scene doesn't over-expose on the waveform monitor. I usually shoot at the V-Log base ISO of 640, and up to the second base of 4000 without noise in the shadows.I mention in either the article or the video that these shots would have benefited from over-exposing in camera when using V-Log. Admittedly I should do another shoot and try to do better by V-Log. But my time is limited for such things.