You are probably going to have to combine a few different products to get something strong enough.

Start with an anchor that stakes to the ground at multiple points.

Then get heavy duty ground stakes, at least 14 inches long. If you use the above anchor you will need two of these packs of ground stakes because the anchor has six stake points and these are packs of four. You will need to carefully start getting the stakes into the anchor above ground, because the anchor is designed for straight screws (which are weaker). Then you can screw the stakes into the ground. Alternatively, you can screw the stakes all the way above ground, dig an 18 inch hole, fill it with cement, and put the stakes into the cement with the anchor on top tied to something so it does not sink.

You will also need a cable with a shock absorber, don't get a bungee leash, they have too much elasticity and can break.