Does King's Huntsman have to roll a 6 to hit like everyone else....or might his Special Rule kick in, maybe needing an extra In The Way against SL? His rule is so close to Legolas's.... What would a GW ref rule?

There's nothing for them to rule as the Huntsman just fails in the way rolls on a one which has nothing to do with hitting Shadow Lord on a six.

You're right. I was more hoping than thinking.