Sorry, can't see your picture that you posted.... Soooo.
The tech just left. He replaced what he called the "D" board. From his description, it drives all the other boards in the set.
So far so good.
He said that there was no way of "him" actually testing individual boards. He simply replaces boards in the order that Panasonic advises him too, until the issue goes away..... Interesting, to say the least.