Do you, or a friend, have a riding mower? I have towed non-moving vehicles short distances, including up hill, with a riding mower and rope.
It may be possible to get a shaft or drift through the open side of the differential to the opposite side, up against the but of the CV shaft still in it, and bang it out with a hammer. There is usually a large pin for the spider gear that goes straight down the center where the CV shafts butt up into the diff, but there may be enough room to get around it and press up against the edge of the butt of the CV shaft.
Also, do you push the CV shaft into the diff and take the pressure off inbetween attempts to pull it out?
The CV shaft is usually held in by round spring ring, that compresses with enough force to let it slide out. The ring is just big enough, that sometimes it wedge outside the bevel that is designed to compress it and let it slide out. If you have to make several attempts of pushing in and then pulling out before the ring seats all around inside the bevel. If you just pulled it once till it stopped, the ring might be outside that beveled cone and up against two flat surfaces. pushing it and pulling it out again would free it up and get it to fit all around inside the cone/bevel and compress it to finally come out.