I still see the device migration error in Win11, but I’m not sure if that matters.
I had to use the latest Noahlink Wireless Firmware Updater (NLWUpgrader2.24.exe), not the Apr19 version (NLWUpgrader_Apr19.exe). Then use the firmware downgrade method which detected v2.15 and upgraded it to v2.23. From there, I upgraded again to v2.24.
The device was already converted from an Airlink 2 which is why the Airlink 2 Updater did not work.