You created a medicine that can save sick people. Are you forced to sell it to sick people? If you ask for a lot of money, way more than it cost you to make it, is it killing them?
I would say it’s shitty, but you don’t owe people anything.
Now yea, not covering medical expenses for people in life threatening situations is really bad, but doing it when they’ll be okay and have to pay is less evil.
And yea, about the cliff, I believe not helping is not the same as killing someone. You didn’t put them in this situation, and acting could affect you negatively. (But they would suffer a lot more from you not acting)
America needs social healthcare by the government, not private companies