They sound like things that fall under "bad **** happens sometimes" that doesn't make it your fault. I bet before the operation you were worried about it going wrong right? The voices pick up on your fears and use them to control you. The operation would have gone wrong regardless of you doing or not doing what the voices told you.
I think also what you're not focusing on is all the times they've told you they'll do something and then nothing happens. But you're selectively thinking about stuff - there's something called
confirmation bias which it sounds like you're practicing with regards to the voices. The other day you were scared to eat too because of fears about the voices acting against you, did anything happen then? What about all the other times, like (if I recall correctly) when you were worried about someone breaking in - did they?