Well you have something there. Maybe they wanted to treat her more respectfully since she was a nurse. And the story is she was kidnapped to provide the Jihadist brigands with medical assistance. Would you want medical help from a battered whore/sex slave? So they made the whole deal as legit as possible by forcing her to marry one of the Jihadi leaders.
Just my guess of course.
When you have a gun pointed at your head all of the time, most people are not concerned about respectibility. I also don't think that a terrorist who has been holding hostages in the jungle for months is all that concerne about how the world sees him.
All that said, I am very sorry that two more innocent people have died.