Well, since Lemon didn't get back to the dealer on 2/17 for obvious reasons, it got dropped back off yesterday. They did another software update and "are confident that will fix the issue". Since I couldn't pick it up yesterday afternoon, I left it there, and the service advisor started it this morning to check for errors, and nothing. So we'll see. However, I am not confident.
If the errors do persist, the next steps I'm going to take on my own are:
1) Put in the Odyssey Red Top AGM battery I have in my garage (never moved it over, and should be healthier than the OEM one), along with disconnect the parking mode on my dashcam. That way can eliminate it being a voltage drop issue.
2) They also brought up all the extra wiring in my hatch, which is for the Euro Tail Light harness. While they acknowledged it's probably not related to that (and I agree, it just splices into the 3rd brake light and 12v socket in the trunk), they did ask if I'd be willing to unplug it and put the stock taillights back just to eliminate that as a variable. I get it, they need to cover all their bases. Said sure, they've been pretty good to work with, so I don't mind.
If it does persist, doing those two things should eliminate any concern of mods interfering, or it being a battery related issue.