I've been on all sides of this, union, non-union, hourly employee and management. I can assure you that if I wanted to get rid of a union employee there are ways to make that reality. You rarely hear of the failures of a union to protect employees, only their successes. There are plenty of good examples of both sides, but there is no absolute security blanket from paying union dues.
In the case of the Greentree employees, I would suggest that should they want to push for change, they get their info assembled and their support lined up, then get this to the news media anonymously. I say that since I have seen no evidence thus far that the government agency(s) responsible for effecting change are doing their jobs. While everyone may be playing a waiting game there doesn't seem to be much activity from the political side either. That makes me nervous as to the agenda of our elected officials. That would start at the Fox Township supervisors and go through Elk County, Harrisburg and beyond.