When you do big parties like that you don't just randomly distribute servings. I'd have the overfull, 100% real, ten minute old OJ for the guy with the really particular request and could end up serving sunny delight to the cheap seats. To serve 700 people a drink takes a considerable amount of time in and of itself so you have more breathing room than you expect.
This is really common. When you do a wedding the bride and grooms table gets the best looking portions you have, the table next to the bathroom isn't so lucky.
The requirements were clear and specific and you cheated to achieve the goal you assumed, not the goal that was stated.
He also has no clue that it's 2 hours old or 4 hour old.
What he really wants to do is tell his guests "this was fresh squeezed, two hours old" and he will get what he paid for, just like his Maine lobster (thats probably Russian) or softshell crabs from Alaska (China), or Key lime pie (Chinese lime juice). That's how the resturant industry works, this test is useless there.
willcipriano: "This wouldn't work on me, because I'd just do fraud"
If he vendor has to hand squeeze it might be 10$ if they have a machine its 5$ but either one is a valid quote. If someone says no problem we can do it no solution steps are provided then your vendor didn’t examine the problem sufficiently. Keep in mind this was 1980s when auto juicers weren’t common. In modern times a large venue might just be able to do it without any additional expense and absorb some of the cost because markup is high enough