How to suppress window using wall clock time instead of event time in Kafka streams?

The requirement is to send alerts if the expected 'final' event (identified from the evenType field in event payload) is not received for a key within a time window of say 2 minutes on the input topic. I tried using suppress() as follows:

events
  .groupByKey()
  .windowedBy(TimeWindows.of(Duration.ofMinutes(2)))
  .reduce((oldValue, newValue) -> newValue, Materialized.as(....))
  .suppress(Suppressed.untilWindowClose(BufferConfig.unbounded()))
  .filter(event -> !event.getEventType().equals("FINAL") )
  .toStream()
  .foreach( /* Send that email! */)

based on this blog.

However, since the suppress() is based on event-time, if the next or the 'final' event is not received, the time doesn't progress and the alert is not sent at all. How can I use wall-clock time with suppress() to emit the event when 2 minutes has elapsed based on wall-clock time?