A limitation (for safety reasons) is that you cannot compare username data so cannot have custom logic for certain players. My recommendation is hide a secret trigger or button somewhere or have a room that you need a code to get into, here’s a tutorial for something like that: https://www.youtube.com/watch?v=UbtznLrjtl8&ab_channel=KivxnUEFN
Either add a way to cheat in your map (a hidden mutator, a pinpad device, an hidden button) or use a persisted switch_device to register yourself as an admin on an unlisted version of your map, then hide the switch_device / make it not interactible anymore, and you’ll be the only one with the switch enabled on the listed version of your map