My experience with Apple is that they do what they want and getting anything out of them occurs on their timeline. If you don't like it, get stuffed, they won't budge.
Seems to me the client got the work for nearly free (gaming the system time only) - I see nothing in the article about UPWork requiring the client return work product as consequence of payment refusal.
Sure would. If that would pass, I would simply create a club, let everyone join up and call them members of my organization and ship apps through it, bypassing Apple, the 30% and App Store review all in one shot. Considering how I've been treated at the hands of the iTunes support team, I'd do it in a heartbeat.
They know how many installations are active and how many people work for the org. When wildly out of line they could send a lawyer-gram and then shut it down if they don't get a response that accounts for the difference. Enterprise apps still phone home to the mother ship (Apple) and will refuse to run if, for example, the device doesn't have an internet connection for some number of days. (90 if memory serves.)
My experience with Apple is that they do what they want and getting anything out of them occurs on their timeline. If you don't like it, get stuffed, they won't budge.