I completely forgot about Acidified Copper Sulfate
https://aliveterinarywisdom.com/use-of-copper-sulphate-in-poultry/
I used this on my hen when she had sour crop fungal infection it cleared it up,
I wish you'd look at the names of this drug I am pretty sure you can buy lamisil over the counter
https://www.rxlist.com/terbinafine/generic-drug.htm
@Tales from Duckingham
@New duck mommy 2021
@Tales from Duckingham do you have Veterycin. After bathing get some good pics but I’d also spray may help relieve some pain until you can decide how to treat.