Thanks KC. I think my question description was not clear. What I am trying to finalize is the
fireproofing of the propane fridge compartment area, upper part in particular, not the cooktop(which has its own heat screen/cover).
Here is the picture of the fridge compartment area. The fridge's propane torch fumes and electric heater will heat the upper vent area surface and therefore it needs some fireproofing in that area top and sides:

I could not find good info online for what are good materials would be, the fridge installation instruction calls for "fireproofing" material or cover, but then too many pictures of failure and propane fridge fires or lack of fireproofing in the fridge upper vent areas. There will be no contact with food from that hood, since it is hidden under the countertop. Hope it is more or less clear now. Like with any fireproofing, "it depends" what are we proofing from and for how long. I want to be reasonable with fireproofing and still be safe.