If it were me, i would use an eye dropper and give it a drop or two of oxytetracyclene and a drop or so of water to keep it hydrated if it isnt to far gone.....Any other with suggestions feel free to chime in.
Levamisole was used as a human dewormer for many years and is still used in some countries. I would not be worried to consume it in a residule low level poultry/egg situation.
Im sorry to hear of the problems your having with your peacocks.Their is a section of the forum devoted to these birds if you want to check it out. Most of us here are familiar more with chickens and chicken related illnesses,so its hard to determine whats wrong with your pea fowl. I hope they...