I''m also confused if this is the silence that was being talked about? The fall of the Eleventh seems to be a different event to the fields of trenzalore and maybe 'The Silence' refers to the event where the Doctor actually dies as the point when silence falls, not the crossing time stream incident that we saw here.
The fall of the 11th was the TARDIS falling out of the sky over Trenzelore.
"Do we jump?"
"No... we fall"