I suck at moving shots with a muzzy. I don't know why and am a good shot with a rifle on moving shots and good with a shotgun. Not so with an open sign muzzy.
I'd pass for now. I'd be ready to shoot if he gave me an opportunity after he crossed the fence and would try to stop him with a cow call. With a gun, even a muzzy, he only needs to stop for a second or maybe two. If that didn't work, I'd go kill him in the timber.