Somehow, I ended up having Raul's .44 and his lead pipe in my inventory, despite the fact that (to the best of my knowledge) neither can be removed from him. They don't even show up as being equipped by him, but they somehow made it into my hands. The issue is, I can't give them back...the only option for the two items was to drop them, but it won't let me pick them back up again. I gave Raul another .44 and some ammo, but I'd rather he ddin't waste my resources. Any fix to this (or at least a way to prevent it in future playthroughs)?

Is the name actually Raul's .44 or just .44 pistol?

Just .44 magnum, but it takes a unique ammo type which I assume is companion-specific (in that they have an invisible, infinite supply). Think the ammo type was "MCA", or something to that effect.

When a companion gets disarmed (weapon knocked out of their hand) they don't go back for it. So it is lost.

There is no way to prevent it currently, other than watching out for it.

You probably went into a casino on the strip with him in toe, they took your guns and his. Then when you exit the casino your guns and your companions guns are put back into your inventory. You can give it back to him via the companion inventory screen.

Regrettably, that didn't work for me. I actually got his .44 and lead pipe at two different junctures...meaning, he was gimping around with his lead pipe for a while after his .44 disappeared, until eventually even his pipe appeared in my inventory. I'm not sure how it happened - if they got knocked out of his hand, I never had to pick them up off the ground. Mysterious.