The exclusion of the Canadian woman is a crime on the basis of the USA juridical system. And if I am not wrong the jurisdictional authorities having competence on crimes committed in the UN headquarters are the USA ones.We should then act against those persons who have the responsibility to have discriminated a person just for her being a tibetan.
She - at leat - should act, calling those individuals who are responsible in front of a judge.
I'm sure that it would be useful to verify which penal rules are in force in the "UN soil"; and we should act in consequence. In USA such a behavior is a crime: and it is sure.