A1706 - Critical software update

[overshoot]

Another A1706 Macbook 13" Touchbar with the deadly "Critical software update" error.
I've tried unplugging the battery and using another known good touchbar but no luck.
We've also tried to access the drive using the Apple Data recovery tool connected directly onto the lifeboat connector and drive would not show up.
Logicboard is in pristine conditions...
Can I assume his drive is dead?

 

[2informaticos]

If SSD is not good, or deleted/formated, touchbar driver is also lost...

 

[overshoot]

SSD is not showing up in recovery mode nor will show up with the Apple recovery tool (tool still working as tried on another board).
I've tried every combination with and without the touchbar plugged in.

I've measured some rails from the Piccolo chip and they all seem present.

Controller and NANDs are getting hot.

Anything else I could try you think?

 

[2informaticos]

Did you connect metal plate of Lifeboat connector?

Try an USB OSX, let see if still complain about driver needed.
Or try to do fresh install to an USB SSD/pendrive.

 

[overshoot]

Metal plate of lifeboat connector is indeed connected.

We've tried all variants of OSX to boot from but it always leads to the critical update error.
OSX won't boot.

 

[2informaticos]

Try the steps already posted in other threads.
Be sure you can get acces to Apple network mentioned there.

 

[SMMRepair]

Make sure your trackpad and trackpad cable are both working and not gunked up. These units will boot to the software update if there's a problem with the trackpad, FYI.