I don't have goslings, but I've raised three ducklings. They were a day old when we first got them.
They weren't interested in the chick starter until I made it soggy and put a bit on my finger and poked it at them. Once they all started eating it off my finger, (maybe it looked like a mama duck's bill?) I lead them with my finger to the food and they finally started eating it. They wouldn't eat the dry food for about a week, only wet.
They also loved bits of greens in their water every day, and chopped up tiny bits of bologna or hot dog, too, though that was only once a week or less.
Maybe these things would work for your gosling. Good luck! We're hoping to get goslings this year. We love our birds!