A few of my past dominion games played there were yoricks playing, they always go bot and push it so hard that the other team needs at least 2 people to defend bot. Ive never seen a yorick lose on dominion
nunu does surprising well against yorick aslong as you're not afraid to get in and auto attack him.
Nunu is a counter, but he can't do anything with all the farm he gets on top lane.
But you could send a tank bottom as support (Leona, Taric) and get someone like Lee Sin or Xin Zhao (or any bruiser) in the jungle and try to get the jungler fed with ganks on top lane. Nunu has very strong gank assisting power.