Firmware problem or issues with WD30EFRX-68EUZN0 on Mac

I support the SoftRAID for Mac software and am trying to help a mutual customer, with lots of WD drives, but a set of 4 that do not work in the Mac.

SoftRAID creates RAID volumes in Mac OS X, and a limited version of the SoftRAID driver is bundled with all OS X installs, so the driver passes all Apple QA testing as a kernel extension. There are no compatibility issues with SoftRAID and OS X. We have thousands of users who use various WD drives with SoftRAID.

The only significant differences between OS X (disk utility) scanning the drive and SoftRAID, is SoftRAID sends multi-threaded queries to the drive and does a SMART query. I had the user disable the SMART query, so that should not be the issue.

The problem is specific to WD30EFRX-68EUZN0 drives.
The firmware version on the problematic drives (all 4 of them) is 07.01E.8

I have isolated the problem to the specific firmware on one of his sets of drives, version 07.01E.8.
Drive models with this firmware do not work in the Mac with SoftRAID. The disks hang when queried.

He has several 2014 models of this drive that work fine and several 2018 versions that work.

Example:
WD30EFRX-68EUZN0 manufactured in 2018 have multiple firmware versions, that work:
The firmware versions are 82.00A82 (2015) and 80.00A80 (2015). No problems at all.

The user is in Italy, so it is not easy for me to obtain the specific drive to debug this.

My questions are:
Is there a firmware updater for this model drive that may resolve this problem?
(needs to run on a Mac, or an ISO Thumbdrive image that can startup his Mac.)

If not:
Is there anywhere I could purchase this specific drive AND firmware version to test it?
(or get a loaner from WD)?
Once we obtain the drive, we will figure out the problem and report it to WD, so a contact would be useful, or I could post it to this thread at that point.

thanks!