Homekit App has No integration with other vendor Honekit devices, scenes, rooms, etc.
New Homekit enabled bridge and dimmers all setup. iOS Homekit Apps are supposed to automatically recognize devices and scenes and rooms from other Homekit enabled devices from other vendors.
Only the Lutron gear is shown in the app (dimmers and Pico remotes).
The Lutron app apparently doesn't have Room management.
Why is the Lutron Homekit enabled app not able to see other HomeKit devices from other vendors?
If you are curious, download the Elgato Even iOS app and look around to see what's where.