Justme69, all what you say makes perfect sense.
However, nobody so far has been able to confirm how a probe heater malfunctioning (overheat or what else) would lit some light (which one exactly ?) in the panel.
Another unanswered question is about layout of the CBs, which ones are close to the one controlling RAT heater ?
Certainly these are not crucial questions now, but having a definite answer would help dispelling rather than supporting certain theories.
On the investigations side, I learn from Spanish media, that Spanair had denied relatives access to CVR recording, meaning it has been listened already by someone. Consequently, the box reportedly damaged is the FDR, hopefully useful data can be extracted anyway.