Hi Cristy,
Yes, you can use the peroxide to clean and disinfect thearea. No need to dilute it with water.You'll definitely want to keep it cleaned out. You'll have tobe careful of inflammation. You can also use an antiobioticcream. Use the peroxide first, then the antibioticcream. Some folks have used human anti-fungal powder from adrug store.
Because pain causes stress and candepress theimmunesystem, I would get some NutriCal for Roger. It can bepurchased at a pet supply store, or a feed store for under$10. It will help boost Roger's immune system, as well askeep his appetite going and get the nutrients he needs in case he slowsdown on his food.
Definitely keep a resting mat down for Roger, be it cardboard or aplastic resting mat with draining holes in it. Stay away fromrugsor towelsand anything that can holdbacteria. He'll need a resting mat of some sort. Ifyou must, you can use hay to line an area of the cage with, but youreally have to stay on top of cleaning it regularly because you don'twant Roger ingesting hay he's used as a bathroom. Be surethat Roger has a place to rest his feet on and disinfect and clean itdaily.
You might wish to treat for parasites or be on the lookout for them ifyou haven't checked. Ivermectin (a greenpea-sizedamount) can take care of a lot of bugs except for fleas in their adultstages.
Keep us posted.
-Carolyn