Nissan 370Z Forum - Weird 2016 Nismo ABS Controller issue

My Nismo is exhibiting an intermittent issue which shows multiple symptoms including:

ABS fault
Traction control fault
TPMS warning
Speedometer & Odometer both stop working
Key fault
Synchromesh stops working
Difficult shutting engine off

When I ran fault scan, I only got the P0500 generic Powertrain fault code and was unable to clear through OBD reader; but was able to clear by disconnecting the battery. The problem occurred a day later with the exactly same symptoms.

My dealer checked it when these symptoms were not present, but the the Consult scan reported low voltage faults on multiple systems. They diagnosed as battery fault (suggesting intermittently shorting cell), and replaced battery (under warranty) - which they also said failed load test. I never experienced any starting difficulty or symptomatic battery problem; but their diagnosis still seemed reasonable at the time.

The problem reoccurred a week later, and I took it back in while the symptoms were still present. They had a tech run diagnosis while car was still running and exhibiting the problem, and found multiple faults again including ABS controller (which also controls TCS). They told me that unplugging the ABS controller removed the other faults (I guess particularly the non-functioning speedometer and problem shutting engine off). They told me that they would have to order me a new ABS Actuator (which I think included the ABS/TCS controller. I considered that this is likely cause if the controller fault is pulling down the CAN bus connected to the other components.

This is where story gets interesting and why I'm posting this. After just over two weeks, my dealer notified me that the replacement part is backordered and is not expected to be available until the end of May (10 weeks) and was unable to do anything more to expedite from their side. I contacted the Corporate office and filed a case number asking for their help to expedite. I was expecting that they could do a broader search across US dealers or even the factory to find one and expedite delivery within a week.

They called me back the next day to report that they are unable to find one in stock anywhere or to expedite as one would have to be built and sent from Japan - which takes 6 weeks delivery by boat. Yes, they really said this. I countered that Nissan is currently building cars using the same part (I've cross-checked part numbers between 2018 and 2016), and that they most certainly must have this part in their factory; so they are simply choosing to prioritize the allocation of these to production rather than cars in the field with a safety defect. They responded that it's just a matter that this part isn't available and would have to be built, they consider this to be an important issue, are prioritizing delivery of the first available to me, blah blah.

I've explained that I consider this a wholly inadequate response and am escalating up the Nissan USA chain to Sr VP to at least express my complete dissatisfaction. As this case is still under review, I'll refrain from commenting further for now; and just ask if anyone else also sees a problem with their response.