Nice post above. But posted after that only for chance. I will only answer about the thread. The other troll like commentaries does not deserve an answer.
According to Commodore Cano (he was CO of C-130 Herk Sqn) in "Recuerdos Transporteros", he saw the gun cammera footage of the SHAR in Uruguay. I have another book in the shelf (but I am not close to it right now) about Hercules in the war and it says that a ex military pilot, then civvie, saw the gun cammera in a convention in the Miami airport.
I donīt think no one in Argentina argued about the legitimacy of the kill. I only heard complaints about it was an overkill, because the A/C was (allegedly) already doomed and on fire, trying to ditch at the time of the cannon engagement.
I must end saying that like 8 o 10 years ago I attended a conference by Commodore Pablo Carballo (CO of 5th Fighter Group in wartime) and he said that C130 TIZA was fair game, but regretted the overkill of an aircraft in fire. The widow of a crewmember was there also.