No idea who those actors are, so I'll say either Joel Edgerton, Ryan Kwanten, Bruce Willis, or Danny Glover. They all sound relatively like the head wolf's actor, at least in the animated movies I've seen with them.

(Joel Edgerton and Ryan Kwanten voiced Metalbeak and Kludd in Legend of the Guardians; Bruce Willis voiced RJ in Over the Hedge and had once signed up to voice Tony in A&O2; Danny Glover voiced Winston in A&O 1 and 2.)

Edit: But honestly, I wouldn't change any of the actors in A&O4. They're as good as the actors in the original, especially in the cases of Daria, Lois, Floyd, and the head wolf's voice actors/actresses.

Ian McShane was an awesome as Tai Lung.