I did get a response from the Reds today and here it is:
Thank you for your note. We are in the process of training some of our seasonal ballpark staff to monitor the TVs in the Highlight Zone for the rest of the season. As with many new features to the ballpark, it takes just a little “seasoning” for us to get the process down to perfection. But, we will certainly get there!
Promotional Events Manager
Great American Ball Park