The brother and the sister weren't standing at the same location. So what she couldn't see doesn't mean he couldn't see also. Stop trying to tell what a witness could see or not see when you weren't even there to be in their shoes and their place exactly when it happened that night.
Even if he couldn't see, you are back to nothing in terms of proving that a gun exist with the boys in that Durango.
And stop trying to squeeze blood out of turnips with the speculation about the actions of Davis' friends. Nothing they did could be construed by anyone of such.
You make a wild claim that "The testimony/evidence is that a gun was seen." Now, show me the testimony/evidence that a gun was seen unless you're referring to Dunn and his gun which isn't the debate here. Link please.
Otherwise you have nothing, nada, zilch to prove your case after leading us into this long journey of wild goose chase.