Thanks and good luck on the bug hunt, let me know if you want me to test anything out on my end.
I was starting to suspect it had to do with the link between the Tinker board - discussed in the other thread. Occured to me that both seemed to be functional, but if it was trying to connect to the internet while booting, it would have to do so through the Tinker board. Any failure at this point would likely result in a loop stopping the boot cycle from completing.
Maybe move the network initialization to the very end of the boot cycle, or disconnect it from the cycle all together (if that is even possible)?
I can also confirm that the reset trick you mentioned in the other thread work for me, but only during a power cycle (power on → hold reset → power off holding reset → power on holding reset → hold reset until LR2 lights solid blue)