I think you should share it with one other person. Almost any other person, as long as you have reason to think they are knowledgeable enough to understand it, and that they will take you seriously enough to listen to the idea. Since you’re talking about a (small) chance of billions of deaths, they don’t have to be ethical paragons—a very high fraction of people will not want that to happen, even if they’re otherwise rather awful people.
This person will then be in a position to give you more useful advice, starting with whether or not your worries are at all rational. (If they’re not, and are instead a sign of illness, then I guess it would be good if the person was not too unkind...)
That was the plan for from the very beginning, but I don’t know anyone like that IRL, and didn’t manage to get in contact with anyone over email or discord after trying several times. Now I did thou, so it’s what I’m doing right now.