in the past people would put a light blue color in the diffuse to offset some skin reddening from using the fast scatter node. turn these to white...or use Snarrly's scene fixer.

 

you should also check out ArtBee's missing manual on corrections. He explains WHY this stuff happens and not just how to fix the problem.

http://www.book.artbeeweb.nl/?p=317

W10, Ryzen 5 1600x, 16Gb,RTX2060Super+GTX980, PP11, 11.3.740