Does this video have anything to do with the 1980 Olympia contest that wasn’t shown on CBS?
Nope! Nothing to do with Mentzer placing 5th at that show for the 7,393rd time

Jim came in with crazy conditioning at the last one they held.
I remember reading that he was around 300 lbs in the off-season before McMahon started drug testing. Quinn insisted that both he and Strydom were tested but, because they were both SUPER BIG, they had size to spare.
He was also adamant that he did NOT follow DiPasquale's high-fat diet. FWIW, Jim Quinn did win the 1990 North American Championship, the year it was drug-tested; Aaron Baker won a drug-tested USA Championships that year as well.