Insider Dev Builds of 21H2 and Windows 11 fail to boot on an Asus ROG G703GXR

I've tried just about every release of 21H2 as well as the new release of Windows 11.

So far, they all react the same way.

Download works fine.

Update during restart works fine.

If further updates need to install, that boot sequence works fine and updates continue to install.

Once it reboots with no further updates to install, the post finishes, there is a bit of disk activity after the post before the spinning circle of dots would normally appear.

That is as far as the boot goes.

It just hangs there, indefinitely.

I've left it sit there for over 48 hours to no avail.

My only recourse is to physically power off the laptop, wait, turn back on and the upgrade is rolled back to the 21H1 installation I am running from the insider beta channel.

The G703GXR is a desktop replacement laptop.

It runs an Intel Core i9, 9980HK, 8 core (2.4Ghz to 5Ghz).

It also has an NVidia RTX 2080.

64GB RAM, 8GB VRAM

1 x Samsung 970 Pro 512GB NVMe for boot.

2 x Samsung 980 SSD 1TB (part of storage space)

1 x Samsung 860 QVO 2TB (part of storage space)

2 x Samsung 970 Pro 512GB NVMe inside ROG ESD-S1C USB-C enclosures.

I've checked and triple-checked all the CMOS/UEFI settings, trying different combinations.

I've gone as far as re-installing from scratch using the 21H1 USB ISO image (which cost me my W10 Pro for Workstations digital license when not all the devices matched the prior install).

I then attempted the 21H2 and W11 insider previews again, same hang at the same place.

What are the differences in the boot sequence for 21H2 and W11 from 21H1?

Is there a way to get any logs or debug information from the boots?