Yes, I was part of Calvin Zane's group. When I hunted with that group for about two years or so, we weren't allowed by the landowner to use dogs. When I hunted with that group, I never heard of anyone in our group shooting hunters' dogs. Neither did i shoot anyone's dog.
I personally saw dogs with tracking collars but never came in contact with their handlers. Since we were hunting on private property, at that time, we were told we should be the only ones hunting in the valley. But we were also told we might encounter poachers which we made sure to steer clear of any confrontation.
It is bad enough anyone's dog is shot. I'm sure some kind of complaint or report could've been pursued, especially in the case of three dogs being shot. I decided to end my time with that hunt because of changing priorities and I no longer could commit the time. Otherwise, I enjoyed my hunts with the group.