Well I did it, though not a full 50-crate sale, it was over 25 crates, which put me in the Screwed Zone.
35 crates, solo, with two Skylifts, from Hanger 3497 to the ship by Simeon's dock and a barge to the northeast of there.
Also brought both Skylifts back to the hanger and had about 50 seconds to spare.
I tried to sell with a random associate twice, but the first time I got 8 Havocs and the second time I got three Moguls. I force-closed the game each time, but I lost a total of six crates, and that's about an hour of acquiring lost, so I brought my total back to 35 for the bonus and tried it solo.
The reward exceeded what I should have gotten, though. I was supposed to get $948,000 but even after Ron's cut I got more than $1.1M. Not sure if the extra was from delivering the Skylifts back or what. I was alone in the lobby.
The extra was the 100% special on Smugglers sales this week, Well done on the sale you was very lucky