Forcing a browser to refresh on a LAN computer via a web interface.?

This is a little complicated and I don't know if there is a way to actually do this without advanced programming.

The applications is an auditorium sign system for a movie theatre. All the signs are essentially web pages built with PHP and MySQL, and using JavaScript to refresh at certain times based on the schedule (for example when the show is seating, in previews, now showing, exiting).

I want to build an interface which will allow me to skip a show (essentially delete it from the database). The issue is I want to minimize the work the theatre staff has to do when skipping a show. Meaning I want them to be able to delete the show and then the signs refresh on their own.

The way the signs are built, they only refresh when there is a status change, as opposed to refreshing at regular intervals.

What I'm wondering is if there is a way to click a button on one computer and have it send a refresh command to the browser on another computer. For example, I skip the show in auditorium 5 from the server computer and it causes the browser to refresh on the auditorium 5 computer. Almost like sending a push notification to the browser.

All these computers have VNC, so someone could log in and manually refresh, but I'm trying to avoid that step.