I don't see yellow feet as neglect/abuse, because no matter how frigging clean I keep them, they still get yellow feet, lol. It doesn't hurt them, just unslightly. I can pretty much guarantee my rabbits would find it more abusive to have their feet washed weekly, lol.
I think peroxide is the same between US and Canada, and when I said peroxide smell... it's hard to describe, but to me, there is a slight, distinct odour to peroxide. I've always had a very sensitive nose(which is weird because I smoke), like, I can smell when a rabbit has given birth. There is a distinct odour(not a blood smell, it's different than that) that I notice when a rabbit gives birth. When peroxide is used on a rabbit, to remove urine stains, it combines and makes a strange musty peroxide-pee smell.
The doe I had who screamed when I used peroxide(this was a couple years ago), it might just have been screaming in shock of going into the water. She had no wounds, no scald, just staining. Didn't have any rashes or hair loss or anything after I used it either, so... It doesn't take much to unnerve me and scare me off something, especially when it comes to something that could be causing pain.
I just need to work up the nerve to clean walker's feet. Probably friday or saturday, so they don't have a chance to get stained before the show, lol.