 if, on or before May 31, 2024, the McElroys upload a Monster Factory video that covers Starfield. 

 about Starfield and its character creator - some kind of multi-game showcase wouldn't count. It can be a one-off video or part of a multi-part series, so long as the series has at least one video dedicated entirely to Starfield.

I have no idea how Monster-Factory-able the Starfield character creator is, but considering the chaos they've been able to wreak in other Bethesda games, it's 

 good material for the series. I guess we'll find out!