If you need to consider the possibility of pressing the button involuntarily, that affects the meaning of the original problem statement. Does “only a psychopath will press the button” include involuntary presses? If yes, then it’s still impossible for a non-psychopath to press the button. If no, then whether it’s better to involuntarily press the button may have a different answer from whether it’s better to voluntarily press the button.
Nothing suggests it’s impossible for him to press the button, even if we grant that it’s possible he can’t reason. Maybe he can stumble into it.
If you need to consider the possibility of pressing the button involuntarily, that affects the meaning of the original problem statement. Does “only a psychopath will press the button” include involuntary presses? If yes, then it’s still impossible for a non-psychopath to press the button. If no, then whether it’s better to involuntarily press the button may have a different answer from whether it’s better to voluntarily press the button.
I’d interpret it that way.
The intended interpretation is that if the person presses the button, they’re a psychopath.
If I press the button, I have always been a psychopath, and I die along with all other psychopaths.
If I don’t press the button, I may or may not be a psychopath, and I live along with all other psychopaths.
All the details you’re writing seem to me to go against the Occam’s razor’s interpretation of the problem.