@NoOneKnows I suspect death by Sodium Nitrite is pretty much guaranteed so long as you don't get rescued and taken to a hospital. Obviously, though, you're right in not trusting a few cases to prove it will kill you. At least, not in a strictly scientific way. We obviously have no way to really know it's a guaranteed death and what the likelihood of death would be based on a certain dosage. It's not like anybody could do any real research into this.
I do know what you mean though, because a huge majority of suicidal people online (who haven't done any research) tend to think you can die by taking huge handfuls of Tylenol (aka, acetaminophen or paracetamol). If you're paying attention, you'll see that there are a lot of people who claim they've tried this method and obviously didn't die. In the case of tylenol overdose, it's assumed your liver will be overwhelmed and shut down. Some people obviously have stronger livers than others and only end up doing major damage to their health.