Does USA to PVG for 4 nights then PVG to USA qualify?

We went from the U.S. to Beijing in February this year for 2 nights, and read the "onward" tix MUST BE different than the country you came from (or else it is NOT transit).

So we booked a day trip to Hong Kong, showed this "onward" tix at entry for the transit visa, but simply never went.

Immigration took us to the side for half an hour and said we were supposed to go onto a THIRD country, and were NOT allowed to return to the country we originated from - we just stood there and looked sorrowful, and they let us catch our flight back to the U.S.

Setting aside the mind boggling set of visa rules, can you answer if our R/T from the U.S. and returning directly back to the U.S. qualify us for our 144 Shanghai free transit?