Apple RAID set Disconnection Errors

I am trying to use an external Thunderbolt 3 enclosure that contains four internal SSD cards. I used Apple RAID assistant in Disk Utility to create a RAID0 using three of those cards and formatted them as AFPS. The fourth card is not included in the RAID set and is formatted as Mac Extended Journaled.

Throughout the day, I randomly experience a "Disk Not Ejected Properly" error on all of the Volumes I created within the AFPS RAID set. The fourth SSD card (not part of the RAID set) does not experience that disconnection error. Once the disconnect error occurs, Disk utility won't remount the RAID set. Only a Mac re-boot brings it back.

Since the fourth card (not part of the RAID set) doesn't disconnect, I don't think this problem is coming from either (1) the MacOS energy savings settings or (2) the firmware in the external hard drive enclosure. Changing the MacOS energy saving settings didn't help anyway.

Based on all this, the drive manufacturer (OWC) seems to think this is a problem with the Apple RAID software. I agree that seems like the most likely source.

Any suggestions on how to diagnose and fix this?

iMac 27" 2020 with Catalina 10.15.7