I have the impression that the bishop was attending this...well...liturgical thing outside of his own diocese. If so, there is precious little he could do about it correctly. He should have inof4med the ordinary, but if the ordinary tolerates nonsense like this already, he most likely would not only not care but be annoyed.
This is not an excuse for the bishop to fail to at least try, but really, for a bishop, he doesn't sound so bad. At least he can recognize a problem when he sees one. Many mitered idiots can't.