looks at rivalry value. USC just pulled UCLA along with it to B1G.
Stanford should top your list of B1G targets other than ND. Why? ND. Stanford has better viewership than most fools in CB realize, but getting ND into B1G May very well depend on landing Stanford - a key rival- and keeping a Bay Area presence better than a Stanford / Cal rivalry pair.
If they take Oregon - it will be a UW / Oregon pair and probably because ND said no - so Stanford was not taken.