Compute Module 4 IoT Router Broad Mini endless PXEboot attempts

Hello.

I have a CM4 with Wifi and eMMC with the IoT Router Broad Mini board and case.

I am able to boot the board and access the eMMC via rpiboot.

I copied the OpenWRT image with:

sudo dd if=openwrt-21.02.3-bcm27xx-bcm2711-rpi-4-ext4-factory.img of=/dev/sdb bs=10M

And added

dtoverlay=dwc2,dr_mode=host

To /boot/config.txt

After disconnecting and then re-powering the device, the image is intact with the modifications and can be mounted by my host desktop (running Rocky 9.5) using rpiboot.

The device wasn't coming up so I set up a test network with a separate DHCP server to service the device. In normal boot mode the device will continuously recycle and request a network boot as "PXEClient:Arch:00000:UNDI:002001". This indicates to me that the device is not booting off of the eMMC device, but defaulting to a Network BIOS boot attempt. I also attempted a flashed Pi image on an SD card and it still attempts only booting from the PXEClient.

I hooked a tty serial converter to the device and there is no serial output at any time.

Is there a way to troubleshoot the boot sequence of this board or force it to boot from the eMMC? The dd image should work properly, right?

Thanks.

--Joseph