Hey there Stephanie,
Thanks for this question - it’s a great one. If your UGS is using the Horde metadata server (which if you’re on a relatively new release with 5.5, I’d expect so), it appears s though UGS’s event monitor will be pushing this to the backend here, with the “heavy” lifting being done here. That’s all to say, you should be able to more or less hit the Horde metadata API accordingly to programmatically set this (POST: /ugs/api/metadata).
I hope this helps (there was no Unreal Engine version listed - assuming 5.5 here).
Kind regards,
Julian