My guess is international law places these people into a particular jeopardy as neither is able to force the other to accept.
Was on a Singapore Airlines trip once to Singapore from US. Plane landed in Taiwan for refueling prior to flying on to Singapore.
A political agitator known in Taiwan just happened to pick that flight to try to get back into Taiwan. Authorities got wind of it and refused to allow anyone off the plane. After 6 hours of negotiations (and us staying on tarmac) in which the US would not fly him back to point of origin(the US) nor Taiwan permitting his entry, the plane flew onto Singapore which apparently permitted entry or otherwise. That passenger was handcuffed to a seat at the back of the plane with a policeman escorting him onto Singapore.
I was headed home from Ottawa via Detroit one afternoon when we lost an engine and landed in I think Toronto. Problem that kept us waiting was that technically we cleared US Customs in the airport in Ottawa (not sure how that works), so they didn't want to let us "back" into Canada.
I knew I wasn't getting home that night, which meant I couldn't make my flight the next morning for personal travel on another airline. So I waited until everyone else got done with their new arrangements, calmly explained my situation to the gate attendant, and mentioned that I had spoken to the other airline and they would honor my return ticket even if I missed the first flight. So, if she could get me to any airport around DC that night or the next morning, I could salvage my vacation. No attitude, no complaining, no blaming, no expectations, I just gave her the opportunity to help me if she could. She did, the weekend was salvaged, and in the end it actually worked out better -- instead of waking up the next morning for a 6am flight and all that goes with travelling, I woke up at my destination.
BTW, was your stop in Taiwan or Hong Kong? When I was working out of Singapore, the option was to connect from Chicago via either Narita or HK. I chose whichever one would let me travel on SA and not UAL from ORD. Always better to switch to the Asian airline as soon as possible.