Pathologist Doctor Pasquano emerges from the cellar, declaring that it is so hot down there, and wondering how the forensics team can possibly work there.
Of course, the precise reverse would be the case. A cellar, especially one which had been as well-sealed as this, would remain very cool, despite roasting hot temperatures on the surface. Any Italian, and certainly Pasquano and Montalbano, should know this, because that's why they keep wine in cellars. It can be ruined if exposed to temperatures above about 25 Celsius.
This is also why, in many hot parts of the world, people have traditionally lived in caves or underground. In Australia there is a whole underground town, named Coober Pedy, where it can be around 50 degrees on the surface, but delightfully cool in the homes excavated down below.
Mimi, Beba and Salvo Junior are all very much enjoying their new home, but they vanish totally as soon as it becomes a crime scene, and are seen no more. They are clearly no longer living there, but no indication or explanation is forthcoming for where they have gone.