you will have to use something on her back so she doesn't get a sunburn because unless they are completely pulled out then the broken ones will have to wait until this fall when she molts.
they have bag balm at most farm stores, look up the chicken saddles, it looks bad but don't worry she will heal up fine if it is only from, you can put triple antibiotic on the bloody spots and she will heal up fine, one of my chicken hens got sliced so deep you could see the tissue that covers...
If she isn't ripped open then put a saddle on her, a chicken saddle should be able to be adjusted to fit a duck, it sounded like she just had her feathers pulled, can you post a pic?