I don't know the laws in your area. You could find yourself in a lot of hot water if you capture the hawk. I think that if you talk to the fellow that he will tell you that he can't help where the hawk flies. Sorry but I don't think you're going to get any help from him. Netting works great. We also have geese in with our chickens. I have been told that hawks will not attack when they see geese because they are too large..
Just a few miles from here, the region has erected a board and a skid onto some very high poles next to a large river. This was intended to attract bald head eagles. Well it worked. We have a pair that has nested there and has youngsters on a regular basis. Beautiful to watch. Problem is many of our friends that live in the area are being bothered by the eagles. Nothing they can do about it. You can't control where a wild bird flies. Hawks, even if being rehabilitated and eagles are in fact considered wild. Sorry, probably not what you wanted to hear.