My Chocolate Runner hen had that last summer. She didn't have any pus either. I applied neosporin every day, and she was running around like normal in a day or two. I bet Mingers will be just fine!
You could open that up with a sterile shape object, a sewing needle or exacto blade held over a flame. Wipe off the pus with cotton dipped in alcohol, iodine, hydorgen peroxide, whatever. Then bandage. Sometimes those local infections grow kinda big, but if you just open it up for them...