Just that experience proves that often what really happened is exactly or very similar to what any reasonable person would have guessed based simply on the circumstances presented.
Are there exceptions to the general rule? sure.
Again, what do the circumstances indicate? If you are among a group involved in a fight with a person who is shot shortly after that, then circumstances indicate that you probably have some information about the shooting. That's it.
Are there other circumstances that you are using as a "reasonable person" to draw conclusions beyond that. As far as everything I've read goes, we don't know the circumstances beyond him being with the group when it got into the street altercation and being identified being in an elevator with the group. Anything else is speculative.
The general rule is don't assume anything beyond what is known.