Dingbat elder's personal opinion.
He's realized the impossibility of proclaiming a "worldwide witness" (my rough estimate is that at least half of the world's population has never so much even met a JW, much less "received a witness"), so he has taken it upon himself to tell the congregation "here's what Jehovah really means to say".
I suspect he did it to experience the reaction you describe - to hear excited gasps of approval. It feeds his ego, makes him feel important and special for a few minutes.
I'd bet he makes such important proclamations in nearly every part he is assigned.