I personally have never cut the foot. I soak with epsom salt (REALLY soak it long) and gently PULL it out. It might not happen the first soak but it does happen. In the meantime, I put on Neosporin or something of the like and keep them in quarentine... not because it spreads, but because I can clean the bedding daily.
Keep it clean, keep soaking. Tweezers and a steady hand and you can pull the "plug" out. Once it's out, I stuff it with Neo again and keep this up for 10-20 days depending on how bad it is. If it is really bad I MAY give anti-biotics to help the chicken out, but usually that is not something I jump to.
I hope this helps. You will have to do each bird individually and if you have someone to help, get them to. It takes me 20 minutes or so PER bird for soaking and neo alone... then you have to clean everything the bird touches with the bottom of their feet too. Very time consuming. Good luck!