Nice one @Sciborg - yes, I had syllable-based tic-tac-toe down but I was using a 1-9 coordinate system, which works perfectly for the first game but falls apart for the second. Glad someone was able to nail it down! :)
@JeremyDover LOTGP's chat activity says they'll likely be offline in about 2 hours. If they haven't posted by then, would you mind taking their place for the 12th?
@Stiv Glad it was a good puzzle - part of the reason I gave two games was to help eliminate/test possibilities. I figured there were probably some games that could work for one of the rounds but not for both :)
They could of course theoretically be feeding seabirds on Midway Islands right now, in which case it would be Sunday 8am for them :) But I'd venture to say their activity suggests otherwise.