Thanks for the attempt !
It is really more obvious on people skin, but if we zoom a little, we can compare the result between LightRoom and your RawTherapee processing (left if LT, right is RT):
The result with LightRoom seems to be more pleasant to the eyes.
Again, I don’t want to appear as a pixel peeper/snob zooming like this, but the difference is really visible without zooming too much with people face.
I don’t really mind working a bit more with RawTherapee to achieve a similar result with LightRoom. But so far even after having spent hours, I couldn’t achieve as well as 5 minutes with LightRoom (as a total noob, I only installed LT to have a point of comparison, but never actually used it before).
I must be doing something wrong, because nobody else seems to have problem with RT noise reduction.