Maybe if the 2 of you catch her you can video her condition or any injuries to show to the vet and see what he thinks if anything can be done . Good luck I hope you can help her thats very kind of you to try oh and bring some lettuce or something :love
Do you have a friend or family member who can go with you to check on the goose? Or perhaps even ask the farm vet to come with you to catch the goose and check it out?