Don't forget: Zakharova used to be a member of the ruling party fraction in the Duma (Russian parliament), which, I think, explains a lot in her behavior and attitude. She sees herself not only as a ballet star but also as a Big Boss, so for her getting the opening night is not just a seniority issue, but the indication of her overall status with the company. That's why, imho, she just could not afford to take 'no' for an answer.
Somebody mentioned Lane's approach but just imagine what would happen if S.L. were a congresswoman (let's say, the head of the Means and Appropriations Committee ) and were still denied a role she craved to perform. Would she just wait humbly? Or would she use her connections on the Capitol Hill or even in the White House to get her way?
Nah, only in Russia
P.S. It is now very interesting to see who will be opening the tours in London and New York. The administration will not have the excuse of 'this is the decision of the Cranko people' anymore, so they can't hide behind it no longer. Neither can Zakharova, of course, which makes both sides' positions much more difficult.