We had a similar 'skit' in our KH a year or so before Armageddon (Version 1975.10).
I was a Reg. Pioneer and a true believer. The CO/Elder ? (don't remember which) interrupted the school, talked briefly about Noah's day and how the KH's were today's "Ark". Then, he asked the Elders at the back of the hall -- to LOCK the doors ! They did, then stood guard to keep anyone who might want to come in, outside.
He got our attention, then announced, that the GB had just given these instructions to Elders all over the world. The End -- was here.
The first thing I did was to look, thankfully, at my mom & my sisters sitting with me, then at some of my friends. Then, I thought in a panic about my Dad and other siblings & relatives that had rejected Jehovah -- the God of Love. I thought how sad that they would soon be dead. No one else could 'enter the Ark now.
Then, he gave us the 'punch line' to his joke...something along the line of "...aren't you glad you were here ? On time ? This is the way it could happen, bros. & sisters..."
We all breathed a sigh of relief -- and went on believing the same shit -- just more finely tuned. (paranoid)
I had forgotten all about that incident. Wonder if they still pull this stuff ?
Rabbit