Donovan's Bartering Logic was Flawed
I came to the Bridge of Spies Message Board expecting to see an explanation for why the two for one swap was successful. However, I don't see any discussion on the topic.
As stated in the topic line, Donovan's logic was flawed regarding the two for one swap. He was offering a single consideration (Abel) to two separate and distinct parties (the Soviets and the GDR). By swapping Abel for Powers with the Soviets, he wasn't able to also provide consideration (Abel) to the GDR for Pryor. Nothing in the movie lead me to believe that the Soviets were bound to release Abel to the GDR. The movie also went to lengths to suggest that the Soviets might kill Abel if they believed he had turned. If they had killed him, the GDR would not have been able to reunite him with his family via Vogel. Therefore, the GDR had no reason to make a deal with Donovan.
Did I miss something?