My Twitch auto-emails say that Ethan started at 12:00 AM, and that Jeff's morning session started at 9:59 AM.
If Ethan's 7:17 video timecode corresponds to 7:17 AM (which it must), then he got his kill screen over 90 minutes before Jeff started playing.
Plus, like I said, Eric had already announced this score at 10:39 AM. He did not mention that it was a kill screen (possibly because Ethan didn't claim the bounty?)
Jeff said that his KS was his first game of the day, and his post announcing the kill screen came at 12:28 PM (2.5 hours after starting the stream sounds just about right).
874,400 Killscreen
So if I'm reading the situation correctly, Ethan was indeed first. However, as stated in the tournament rules: "Contestant is solely responsible for specifying which bounty they want to claim when they submit a score." Perhaps Ethan wasn't aware that he was first, or that he had to specify this?
Also, before 9 AM, Svavar mentioned having gotten a kill screen as well, but the stream malfunctioned.
Sucks that these two missed out, but them's the rules I guess.
(Incidentally, I would recommend
Ethan's kill screen (@7:17:15) to whoever is reading this. It's pretty funny. Made me feel better about bumbling the recent one I got!)