Personally I would not put ANY creams on them at this stage. It would just flatten the surrounding fur which would mean the area is even less protected.
I would get him off carpet ASAP. You could cover the carpet with a cotton sheet.
ETA- To show you some examples of Rex Hocks...............
Miss Bunny Penny is coming up for 11 years of age. Her hocks lost a lot of fur when she was about a year old. Now the skin is sufficiently tough that she has not required any treatment for her hocks for about 5 YEARS. She has never had any infection in the hocks and her condition has been managed mainly by husbandry (soft hay bedding).
Similarly my other Rexes whose hocks have a varying degree of 'issues' are all mostly managed without the constant application of creams
Sir Victor
Michael
and to show that not ALL Rexes get sore hocks
Brian
Dermot