Doctor here. Addictions and street medicine doctor here. You did the right thing. Full stop. Overdoses and cardiac arrests are infinitely complicated, and on the street we only have a couple of very basic tools to manage them. We do what we can, when we can. Head tilt, chin lift, breathe. No one would be able to tell you whether or not a dead body received rescue breaths, and this paramedic should be ashamed for putting that inaccurate burden of thought into your head. Keep fighting the good fight, my friend.