The general idea is that an exploitable remote code execution bug is some specific circumstances where the processor starts to execute whatever is in some wrong

The general idea is that an exploitable remote code execution bug is some specific circumstances where the processor starts to execute whatever is in some wrong address which can be manipulated by an attacker. If the bug is successfully exploited, the attacker arranges so that everything is just so that device runs "as if normal" but executes whatever code attacker decided to be executed; but if the bug is triggered accidentally or without a working exploit, then it attempts to execute something random and that results in a kernel panic. So the way how "malware prevents a kernel panic" is that it's a successful exploit if and only if it manages to ensure that valid (but attacker-controlled) code runs and actually works, and if it instead results in a kernel panic, well, that's not a working malware, unless all the attacker wanted was a denial of service exploit.