I don't know but I wouldn't necessarily assume that all comfort ventilated seats were nappa; a different model, so not directly comparable, but the C207 E-coupés could be optioned with comfort ventilated but only with either leather or nappa leather.
The W221S-class could have comfort ventilated seats with leather, or the Passion Leather, or Exclusive Passion Leather seats, though I can't recall whether nappa was the 'base' leather; I don't think it was.