Westbrook isn't the problem.
The coaching staff is (Donovan) an was (Brooks) the problem.
Oklahoma has done a horrid job of developing Ibaka. Ibaka has improved his jump-shooting only to be relegated to a more and more peripheral role offensively because of it. The three point shooting is good but it's not worth losing Ibaka's midrange shooting, cutting, occasional post-ups and offensive rebounds. The coaching staff has done a terrible job utilizing him.
Ibaka is right to be unhappy with how he is being treated. He should be furious. I'd be angry if I were constantly undervalued and ignored too.
The coaching staff have also done a terrible job developing Ibaka's passing, rebounding and post skills for several years now. Oklahoma has gotten much less out of Ibaka than they should have. Which is also true for Steven Adams and guys like Jeremy Lamb. Their wastefulness and poor coaching is the biggest reason they have fallen behind Golden State and San Antonio.