They recovered the round that went through the cinematographer and the director-— and went a long way behind them. Great ballistics work— even a deformed round 1/4 mile behind them could be “matched” to whatever was “on the table” Metallurgy of the projectile.
Also— were they ALL stoned?
I heard (though without other verification) that the fatal bullet was surgically removed from the director rather than having to be found after passing through both victims.