I had a goose like this. (Usually if it´s leg problems, it´ll be niacin that´s needed.) I opened her bill and made her eat soaked(a bit soggy) non-medicated chick-crumb (has lots of good things) mixed with brewers yeast, then I put a little water in a bowl with some cider vinegar and floated pieces of lettuce in it, so all together, she was getting (if forced), the important niacin in the brewer´s yeast, other minerals in the crumb, greens, and liquids. Geese generally can´t resist greens floating in water. Also I´ve given them water cress, as that´s also got lots of goodies in it. What else are they eating apart form the corn and hay? They need greens, most important, and corn will keep them warm, but it doesn´t have a lot of good stuff in it. Greens are so important. If it were me, I´d try the brewer´s yeast mixed in with soaked chick crumb and pop some lettuce in a bowl of water. See how he goes. And do the same for the gal.