In other words you have no clue how law or investigation works.
Social media posts can be very useful in a number of ways, including --
- Identifying possible witnesses.
Law enforcement might have no idea that the OP exists or that the coworker discussed the gun matter with him. They know now, if they find this thread (or the thread the OP started on TFL).
And LE might be very interested in what the coworker said to the OP. The coworker might have told a different story to LE. But in any case, any possible witness who could either corroborate or impeach statements made by a person of interest can be useful.
- And if anything in the OP's post is inconsistent with the story the coworker told the cops, the cops will want to know.
- And while it doesn't look like an issue here, social media posts can help provide evidence of motive, intent, or state of mind -- any of which can be important in a criminal prosecution.
So it doesn't appear that you have anything to contribute to this discussion.