Firearm laws are no joke & not easily walked away from,FYI getting caught with an illegal firearm in the commission of a felony is a 2 year sentence with no good time & no plea bargin,just 2 flat fukin years,he could hire F Lee Baily as his attorney & he's still doing 2 years,no way around it.
Does his family have access to large cash for a bond of $100,000 or more,courts do not give out Personal recoginance (PR) bonds on felony weapons charges.
Ask yourself this,why would any man charged with trafficing firearms be walking around on the street a free man,i think you'll answer your own question about what to do.
I'd burn everything if it were me.