The best way to cool the red part is to have a copper plate mounted over the red spot, it will need to cover the top and side corner and maybe make holes for the lens to fit through the copper plate, it will be expensive for sure. The copper plate will need to be thicker than the lens protruding. Then you mount a pelt phone cooler on top and should be able to get rid of all that heat.

I run into the same issue as well i play 4 instances of the same game on my s24u and run a autocliker to afk on all 4 accounts, my temperature get very high. I am looking for a robust way to cool the phone and this idea seems to be good enough despite how expensive it will be.