/sbin/shutdown STILL not working (NetBSD-9.2_STABLE)

I've been trying to upgrade my main server to 9.x since early this
year, first with 9.0_current, then 9.1_current and last week,
NetBSD-9.2_STABLE.  All three of these distributions have a glitch
with /sbin/shutdown.  I reported the problem with 9.1 on May 20, in a
post "NetBSD 9.1, /sbin/shutdown not working".  I was hoping it would
be fixed in 9.2_STABLE, but no such luck.

Since I cannot power down the machine remotely, this glitch is fatal,
and I cannot use NetBSD until I can pin down the cause and correct it.
I'm desperate.

To review what happens:
Issue the command '/sbin/shutdown -p now' and the system proceeds to
shutdown normally, but comes to a dead stop without powering down.
The last four lines left on the screen are (same as with 9.1):
acpitz0: workqueue busy: updates stopped
core1temp0: workqueue busy: updates stopped
core2temp: workqueue busy: updates stopped
acpibat0: workqueue busy: updates stopped
 The only way to power the machine off is to physically press and hold
down the power button.

I really have no idea how to proceed.  Would compiling a custom kernel
perhaps solve the problem?  What should I configure differently from
GENERIC?

There is one major difference from previous installs of NetBSD that I
have done.  This is the first time for me to use an EFI machine and
use a GUID partition table.  Would it make sense to try installing
with a BIOS MBR partition table to perhaps work around the
/sbin/shutdown problem?

After 25 years with NetBSD, I don't want to give up now! Any and all
help appreciated.  TIA!

Henry