Updating the thread here: Normally I don't just throw parts at a problem, but I found a screaming deal on some new VVT Solenoids/Valves. I replaced both intake-side valves concurrent with an oil change to make sure it wasn't just dirty oil gumming up the valve. I then drove 3 hours to Atlanta to get a spare key programmed. Everything was good until about probably an hour+ into the drive I got a 1-5 CEL. That was followed ~30 min later by the 6/10 CEL.
After the appointment (I don't think they cleared anything) I started the car to head home: no codes, but same behavior after about an hour of driving. Pulled the codes when I got home and have one 02 sensor code (P1057) and the Two VVT codes again (P1366 & 1368). Car ran fine the entire time, just for the record.
Another thing I did in the meantime was replace the positive battery terminal. Some previous owner or tech had performed improper rituals such that it would not fully tighten on the post. The only ill effect from that was the TCS needed a few yards to reset itself.