What did the referee do? It must've been pretty blatant if the NBA had to fine him. Usually they stick up for their crappy officiating.
He gave a second technical to Doc just because Doc was looking at him, and the ref was at the other corner during the game, a foul was called, I guess the ref looked towards the bench saw that Doc was eyeballing him and threw him out. (bullshit officiating)
Doc's fine is appropriate. If he wants to complain about an official, he is supposed to do it privately with the league office, not publicly to the media.