I helped at Bethesda, normally the morning chapel service. One time I asked Pastor Hal Wimmer, "Who is the guy with the beard?" He said, "You don't know George Lindbeck?"
I did not have him for a class and the only photo I saw was of Lindbeck without a beard.
Wimmer, later a bishop, said, "He was the official observer for the Lutheran World Federation at Vatican II."
Lindbeck was raised in the Augustana Synod and (I believe) attended Augustana Seminary. He finished his work at YDS and earned a PhD at Yale, citing Paul Holmer as a major influence.
Information about Lindbeck