Lower the hot side to 90. It would have been better to know how much of each carpet is in him to be able to make his habitat better. Carpets have similar husbandry but still can be differnt. Example a jungle will need s little more humidity and lower temp then a coastal would.

You mentioned you are treating him for mites? If he has mites that would be why he isn't eatting. Having mites would be stressful. Stress causes snakes to stop eatting.

Don't ever give the carpet a mouse. THey will need rats when they are full grown and you wouldn't want it to get hooked on mice.

First solve the mite problem. Then if you want it to be on f/t switch it over once the mites are all gone. If there was no issue with mites then you probably would have been able to keep feeding it f/t with no problem.