Did I completely tear it down? No. If the bike was 5 years old with thousands of miles I would have, and probably just troubleshot all the way to the end on my own. But I'm not gonna tear down a 6 month old bike that is still under warranty if I don't have to. At the same time if it was something that someone else had seen before that was like "oh yea I've seen that and you can just fix it quickly like so..." I would, vs driving an hour to take it back to the shop I bought it from.
So I posted here mostly to see if anyone else had seen a similar issue with an obvious yea sounds broken or yea its likely X to fix. I guess I was thinking along the lines of my day job in IT, where even my employees will bounce things off of me like "have you seen this issue before" because after having done it for 30 years the answer is usually "yea I have".
The first reply was largely "I'd have to see it to really have any idea". So I made a quick video to try and demonstrate it. That was obviously not illustrative enough to make a determination. So I'll just drop it off. No point risking shooting myself in the foot with the warranty.
Thanks for the looking and trying to help. I do appreciate it.