I “WILL” press the button.
Reason:
OK, so i press the button. I get the million dollars and (under the worst case sscenario) a person very close to me dies.
Now, so many people die everyday (bombs, accidents, medical diseases etc.) What is the proof that my loved one died because of my pressing the button. He/She could have died due to any of the natural causes. And the person who died because of me was someone else i did not know about.
Look, countless people are going to die everyday whether you press the button ot not.
But, you dont get a million dollars everyday this easily. Hence, i will press.