Wtf is headshot role. Also you're too biased towards vitality.
Shox is currently playing support on some maps. While G2 is swapping roles constantly on maps, even rounds so that they keep opponents confused.
Shox is one of those veteran players who have insane nades. Like GtR,Gob B,Karrigan,etc. So shox is much better than Nbk as support.
Also Nbk hasn't proved anything as lead. Shox is hated mostly because what he did to G2 last year. Otherwise shox was so good IGL for G2 in 2017. G2 were even #3 under his IGLing. Also both are shit IGL when they're compared greats like gla1ve,ex6,pronax,karrigan,zeus...
Co-lead isn't required and creates conflicts. Rather pick an IGL in ex6,happy than pick 2 co-leads or a shit IGL who is a fragger.