@Diannastarr What is the name of the drawing salve you used? Was there a scab on the bottom of the foot too?
One of my hens has the scab on the bottom of the foot and swollen, and has a bump between the toes like yours did.
I did a surgery on the bottom of the foot for the second time a few weeks ago, and it helped temporarily. Now it's the same as before.
She defies the normal prevention because there are no roosts, just elevated platforms with shaving on top that are cleaned every day, and she is the lightest of them all.