It sounds like you know his roost tree or near his tree. Also you seam to know where he goes after fly down. Have you tried to ambush him? No calling just sittin waiting for him to come by? It is a BORING hunt but it does work.
Go between point A and Point B, just watch out for the hen. Also on big ole birds like this I prefer hunting after the hens nest up. He will be single and looking for a mate.