I had the power button issue too; got it repaired as there is a 8 seconds lock on it i.e. even if you disable it from mce.ini and its pressed for 8 seconds, it will switch off.

From discussions I had with people back then, this is hard-coded and even using modprobe to blacklist it didn't work. Instead of killing it, might as well get it repaired. Do remember to take this video to the repair shop so that if they are unfamiliar with your device they still can get the job done