According to the Canon Law (Law of the Roman Catholic Church), for that the natural and sacramental wedding be (I mean a valid marriage in function of The Natural Law and the Divine Law - natural order wanted by the Creator, God (Holy Trinity, Father, Son and Holy Ghost) -, It is compulsary and that:
The Bride -The Fiancée and the futur wife - have to be totally free, a volition without pressures from families, friends, clans, groups, laws, States, administrations : See Can. 1103 "A marriage is invalid if entered into because of force or grave fear from without, even if unintentionally inflicted, so that a person is compelled to choose marriage in order to be free from it." Violence and Fear have not to exist. It is a absolute prohibition.
In this case, there were for instance:
Pressure from the civil local law that is coming from the muslim religious law - a approach very far away from the natural law on the agreement about the wedding - This civil law is scandalous, unfair, wrong, illicit, bad and witout effect in the catholic meaning.
Pressure from her family, because in the islam, it is a great shame, a big issue for all the family. In addition, it is a shame for her and more yet for all the rest of the family (there is a superiority of the group, the individual rights are not so important, they are secundary; there is a primacy of collective rights). If no marriage, she could be, may be, I say perhaps killed by her brothers (see Rape and Honor killing in Muslim Society);
There was too, the age of the woman, she was a teenager, 16 year old, she is a girl in the muslim world: no freedom, no preparation for the wedding, how to agree with the rapist. That is against the nature of the marriage. The good sens does not exist.
And there were other impossibilities for that the natural marriage be. See The canon law of the catholic Church.