That is great to hear. I think I'd give her a probiotic if you aren't already since these antibiotics kill off good and bad bacteria.
please keep us updated on how she is doing.
So wonderful to hear a good report, so many of us haven't Vets that will see poultry or the cost keeps us from going that route but your giving us what worked for your duck helps us possibly find meds online that can help ours if we have something like this happen. Dosage would sure help too...
I’d try and treat her before giving up. If you can separate her where she’ll still be close to the flock that should help. Treating not treating always up to the owner.
Could your Pekin gotten bit by a bee or snake? You could try some Benedryl for children and see if it helps.
As for your WH I'd def get her on some meds. of the 3 you have either Sulfadimethoxine or Tylosin would be best to use.
Here is a med chart for dosage...