Rex bunnies can be prone to sore hocks no matter what you do. They just don’t have that cushion of fur there. If they aren’t bleeding, then you could try to soften the area with some bag balm or plain diaper rash cream. A lot of people have had luck with providing memory foam bathmats to walk on. I’m not sure if wrapping them at this point is necessary. Someone else can chime in. But there are sites online that illustrate how to do it. This one has good illustrations: http://www.bio.miami.edu/hare/sorehocks.html

The sores on the middle of the foot look very red and angry to me, I would personally go to the vet to have them take a look before attempting wrapping. My bun Bertha had a sore that looked like that on her foot and it turned out to be a small abscess that needed to be cleaned out by the vet.  The heel looks fine, and it’s more normal to have a callous there. Can you save up some fur from grooming them? It can be the best thing to wrap the hocks to help them heal.

I would get some fleece blankets and vet bed for sure. You need something softer in their cage, and fleece blankets are OK if they get nibbled. Grass mats are also great. The thicker ones can take pressure off the hock by letting the nails sink in a little. There are these inexpensive beds that are meant to go in dog crates that work really well. They are not filled with foam so they are safer if they get nibbled.

The back nails do look long to me, but it’s hard to say. Can you check them with a flashlight? You may need to trim a tiny amount more frequently to get on top of things.