I spent another hour tweaking to correct the worst bits and it looks more natural, even though the skin tone is a bit off compared to the references... Only one wider spec lobe this time : GGX does a very nice job as usual.

Raw renders after a couple hours of tweaking... Trying different HDRs to see hold it holds up. My goal was to test the data set and it is pretty good. Now, in terms of making it look good, there is still a lot to do !! :-)