There are many things that the visitor can say, and the question is to prove that absolutely anything that the visitor says will result in complete suicide if it provides any information whatsoever about the dots.

That sounds about right. But the problem statement doesn't permit the information to be a lie? The info could be "somebody has blue eyes!"

The comment elaborated on the explanation of "non-trivial" and didn't explicitly say you can't lie. Right? Or am I not hearing this correctly?

Some of the questions incorporate a "new idea" or allow you to change elements. Triangle boxes, prisoners who can make requests, tired tennis players.... I introduced a yellow dot or am I supposed to change the variables to two?

There's a discrepancy between the number of visible blues and the number given. Say the person is a blue and doesn't know it. They can count b-1 blues on everyone else. Hearing "r reds, b blues, 1 yellow," he knows he must be either blue or yellow. He doesn't know which. Everyone survives.

Edit: had a paren instead of opening quote.

I'm also thinking it would need to be at least a couple hundred people to be classified as a town. Which then the odds of someone subconsciously counting a number that high in their head is unlikely.

In a classroom with 30 people right now and I couldn't tell you how many of each gender there are unless I actively try. If that meant certain death, why would I count?

You're being downvoted, which is a bit harsh. However, you are thinking about this as a practical problem, when it is actually a mathematics exercise.

The distinction comes naturally to some people, it's a real struggle for others.