1) Estrada WAS considered initially, and 2) the President knew WELL before the public that Owens wasn't interesting in the USSC nomination. [BTW: It seems as thought most of the 'public' here at FR still doesn't know that Owens withdrew her name from the nomination list!]
Owen withdrawing was all over FR, and I never say Estrada's name on a SCOTUS list. That still leaves O'Connell, Jones, Garza, Luttig, Clement, the two obscure late surfacing women, and Wilkinson.