Then those posts are wrong.
If Ducks win, they have the best record. They’re in.
If Ducks lose and WSU loses, then Beavers and Ducks tie. Beavers win tiebreaker because they won head-to-head. OSU is in.
If Ducks lose and WSU wins, then all 3 of them tie. They each went 1-1 against the other two, which is the first tiebreaker. Second record is division record. In this scenario, WSU would be 4-1 in division, and the others would be 3-2. WSU is in.