Custom friendly names entered in through Omada's user inferface for CLIENTS (click on any client, then select CONFIG from the right-hand pop-up, and enter  friendly name over a MAC address), should be saved as part of a backup from Omada.

It takes a lot of time to manually enter friendly client names for smart bulbs and outlets, so to have them lost when importing a backup is quite a downfall. It's important to be able to quickly identify clients on the network when reviewing traffic stats, etc. within the Omada UI.

** After reviewing the backup options within the Omada UI, perhaps this information is backed up when choosing to back up history. I was doing settings only. It is somewhat unclear whether or not custom client names are part of a history backup or should be included in Settings backup.