ST10000NM0016 Tatsu (Fam 97) — OverlayCompatibilityCheck failed + En Tech TIMEOUT after tech unlock

[Skyclad]

Hi all,

I'm working on a Seagate ST10000NM0016-1TT101 (10TB helium, Family 97 Tatsu, FW: SNYD)
using PC-3000 UDMA-E v7.8.21.

The drive had Diagnostic Port Locked. I successfully read the ROM via COM and applied:
"Tech Mode unlocking preparation (patch)(multi-patch)" — all DFW options unchecked.
Wrote patched ROM, power cycle, then "Unlock Tech, drive prepared by utility".

Tech Unlock Handshake: 0xF1D4B759 → OK
Drive reaches F3 T> prompt, Ctrl+A responds with full drive info:

  Package Version: TAAEA18B5.SDNY.PJ0122.SNYD
  Model: ST10000NM0016-1TT101
  Heads: E (14)
  CFW CompileDate: 20180122

But ALL commands requiring the Diagnostic Cmd Processor Overlay fail:

  Overlay PartNum: 10251052
  CFW PartNum: 01220824
  Overlay CompileDate: 20161025
  CFW CompileDate: 20180122
  OverlayCompatibilityCheck failed
  Unable to load Diag Cmd Processor Overlay

This includes: r93, V1, V4, V40 — all trigger the same loop.

Additionally, when PC-3000 tries to read SysFiles via ATA(indirect):
  → "Error executing command En Tech (TIMEOUT)"
  → SysFile 93 opens empty (0 bytes)

So I have:
- Terminal access (F3 T>, F3 2>)
- Drive identified: 10 TB, Model, Serial, FW visible
- NO SysFile read via ATA

 Has anyone worked with TATSU Fam 97 + this specific Overlay/CFW mismatch?
And Is there a compatible LOD/loader for TAAEA18B5 / CFW 01220824 / 14 heads?

Original ROM already saved. 
Thanks so much

[pbzcbf...@gmail.com]

Here is a 12TB Tatsu loader:

https://firmware.hddsurgery.com/dl.php?file=52972&filename=ST12000VN0007-2GS116-SC60-ZJV5M1AZ.zip

[pbzcbf...@gmail.com]

Could we see the original ROM dump?

[pbzcbf...@gmail.com]

What is the manufacture date on the label? Is this the result of a bad firmware update?

Is the PCB/ROM native?