What did Gary Cohen know in advance last night?

My brain just woke me up with this…

The telecast begins. We are presented with the idea that nobody knows what’s about to happen.

The Mets take the field. There is the idea of a “moment” of silence. The Mers leave. As Gary recaps what we just saw he mentions that they took the field for 42 seconds. I will just remind you 42 is Jackie’s number

Was Gary timing the moment of silence? Why would he do this?

If not how did Gary know it was 42?

How did the Mets on the field keep track of time? Is Dom counting one-Mississippi two-Mississippi?

Someone knew something.