How can Jupiter be a methane ice planet if there is an ongoing fusion reaction?

The idea that there is an ongoing fusion reaction in the giant red spot seems to run counter to Jupiter being an ice planet. It would seem like such a fusion reaction even on a planet so large would raise the temperature above that needed for MGH to remain frozen. Additionally, one would expect the extreme heat of the fusion would dissociate the methane gas, releasing elemental hydrogen which would then sustain or even increase the fusion reaction reaction. This differs from the idea expressed in the theory that the fusion reaction is waning