I haven't driven this combo yet but did you try raising the pressure on the hot tyre? That will keep it a bit cooler. Then you'll have to pick a compromise between too much heating for grip and too much pressure for gripthe front left tire was just GONE already in the first lap if I pushed it a bit.
(I'm planning to conduct some kind of "study" of how the grip varies with pressure and temperature and will report if I ever manage to achieve it!)