I am back in San Francisco!
I will try to fill in the rest of the trip chronologically, but the upshot: The bike is in San Antonio getting an engine rebuild, so I flew home with a return date randomly chosen for the 16th.
The San Antonio shop (a huge Yamaha dealer with a growing KTM business) took the engine apart and found there was no oil in it. Since the bike never consumed oil, I must presume that the mechanic at Motoaltavista forgot to refill it. I feel like an utter moron for not double-checking the work. Naturally, the oil pressure light is not working - maybe a burned out bulb.
So, just in case you ever wanted to know: You can run an LC4 for about 700 miles without oil before it fails. Respect.