Thank you for taking the time to write such a well-sourced post on this. I'm glad to hear that this is starting to go mainstream with people like Daniel Tosh, but really this is just the tip of the iceberg. The people on /x/ and /pol/ have been digging into this for weeks, and it appears that there is an entire network of people that leave caeser cypher comments on these strange videos, and their channels usually include an recent, short, eerie video of a child feigning happiness or enjoyment.
Luckily, Youtube specifically addressed these videos in a recent announcement about new guidelines, which said those type of videos are no longer eligible for monetization. But the chorus of odd comments that pours onto these videos makes me think there could be something more sinister lurking underground, and I guess the loss of monetization will give us a clue if and when content/comment/view frequency changes.