When people say on camera that they're not suicidal, but die shortly afterwards do you think they did it or someone else did it?

Depends on how suicidal they are. A lot of people that plan suicide will never admit to it. Because then someone might stop them. The admission to suicidal thoughts is most often a cry for help with follow-through being a result of not getting the help that was needed.

If you plan to go through with it from the beginning and nothing is going to change that, you generally don't cry for help.