The bail for Rodriguez would be refunded upon proof of his death. Leo had no reason to fret over his money, unless the brothers "vanished" the body for some reason.
When Wills is kidnapped from the limo, one of the assailants fires his gun into the air. When he opens the door to the car, you can see the bolt of the gun is back, meaning it's empty. When he reaches into the car, the bolt is forward again.
Just before the final shootout at the cabin, Sam suspects his Mexican driver is reaching for a gun and warns him not to by pointing his pistol at him and the sound of Sam cocking the hammer is heard, but the pistol clearly has no external hammer.
When the assailants kidnap the businessman and shoot his bodyguards in a very public display, one of them deliberately fires several shots with his pistol in the air to alert the public and make them flee, therefore it makes no sense for two of his accomplices to have put silencers on their pistols to suppress the sound of their shots.
When the guys first land in Mexico, they're seen sitting in the back of a cab. Out the back window, on the rear projection plate, you see the Orpheum Theatre in Los Angeles, indicating that the background footage was actually filmed in Los Angeles not Mexico.