Hm. That ForceRefresh message should still get to the client, eventually. It may take the CommandPollInterval, if you’ve set one, otherwise the relay select interval (six hours, by default).
You could also send an Action with the ActionScript command
notify client forcerefresh.
Once you’ve sent the refresh command, you could also manually restart the client service to make it “see” the command/action instead of waiting for the gather interval.