While I do have some experience with kernel code, if there isn't something jumping right at me after some hour of staring at code and maybe inserting some debug

While I do have some experience with kernel code, if there isn't something jumping right at me after some hour of staring at code and maybe inserting some debug statements on a hunch, I might try the other OSes just as a sort of sanity check to see if the issue even exists at all, or if everything works flawlessly. Or maybe it will break in another way and I'll suddenly have a lightbulb moment that helps me identifying the problem better. Could it be a hardware issue? Could it be that just my device is faulty? Just some revisions of it? Generally I switch between approaches as I see fit, on a hunch you could say. There's no point in banging your head against a wall in some dead end for two hours.