Connecting external ssd to ipad 9th gen FAILED!

I have Apple's Lightning to USB 3 Camera Adapter and an iPad 9th Gen running iPadOS 16.3.1. When I plugged the adapter into the iPad it had a firmware update. The adapter is also connected to power from a standard Apple USB-C Power Adapter which supplies either 18 or 20 Watts (I forget which) via a USB-C to Lightning cable to the camera adapter.

I plugged a USB 3.2 Gen 2 SSD (NVMe) drive formatted with APFS with one volume into the adapter but the Files App on the iPad doesn't see the drive. The drive IS recognized on my iPad Pro and on all my other devices. Is the iPad 9th Gen not capable of recognizing that particular drive? Does it need more power? Or is something else broken?

Thanks,

Peter