RD5200 and RN4200V2 fan control under OS6

I was looking throuugh the logs of my RD5200 converted to OS6 and found hundreds of entries such as this:

   Jul 31 01:15:53 RD5200A readynasd[6308]: failed setting new fan speed target: Permission denied
   Jul 31 01:16:03 RD5200A readynasd[6308]: failed setting new fan speed target: Permission denied

Since I have been having trouble with the RD5200 controlling the fan speeds (I have to leave it up to the BIOS), I figured I was onto something. It turns out that while my RN4200V2 units (with the same motherboard) seem to control temperature better, they have similar log entries.

What I discovered is that the native OS 6 systems as well as all the other NAS I've converted to OS6 from 4.2 (Pro6, Pro2, Ultra4, Ultra6) all seem to store this information in /sys/devices/platform/w83627ehf.2576/hwmon/hwmon1 or similar, where the directory under "platform" varies depending on the hardware.

The files have names like these:

   -rw-r--r-- 1 root root 4096 Aug 1 07:00 fan1_beep
   -r--r--r-- 1 root root 4096 Aug 1 07:00 fan1_input
   -rw-r--r-- 1 root root 4096 Aug 1 06:43 fan1_min
   -rw-r--r-- 1 root root 4096 Aug 1 07:00 fan1_pulses
   -rw-r--r-- 1 root root 4096 Aug 1 06:43 fan1_target
   -rw-r--r-- 1 root root 4096 Aug 1 07:00 fan1_tolerance

But the RD5200 and RN4200V2 have those files directly in /sys/devices/platform/w83627ehf.2576, not the /hwmon/hwmon1 sub-directory thereof. Ah HA!  Maybe I found the problem.  /hwmon/hwmon1 and all directories under it do exist, just no fan, power, etc. control files

So, I tried to copy the files into /hwmon/hwmon1. No dice -- access denied. Since I'm root and shouldn't have access denied anywhere, I can only assume something has a lock on the directory. Readynasd, maybe? Should I stop readynasd and try again? But if it is readynasd, and readynasd is the process getting the access denied errors in the log, what's up with that?  Maybe it's just a wrong error -- should be "file not found"?  lsof doesn't seem to think anything is locking the directory.

I have an RN4200V2 not yet in service I can experiment with. A factory default, or even restoring the internal USB boot drive from image would not be a tragedy. But before I stumble around, I was wondering if anyone can confirm/deny my suspect and potential solution.

Yeah, I know; "not supported". But a clue sure would be nice.