wp_schedule_single_event with time() run during the execution of a cron event doesn't appear to be added to and run by cavalcade

Use case is an event which must come after the completion of another event.
example:
`Event_A` calls `wp_schedule_single_event( time(), 'event_b' );`
`Event_A` shows up as completed in the log but `event_ b` never shows up in the log (neither the DB log or a piped to log from the cavalcade runner).