Well if living outside of Ireland disqualified you from being a human being, 99% of the world's population wouldn't be one.
And I don't believe the children face a danger of FGM if returned home. There is no evidence that any of PI's children that can be proved actually existed underwent it, and one of them was 6 on arrival in Ireland. I think the fact that both the parents are against FGM means the children will be safe. If one of the parents were pro-FGM, then there might be a stronger case for arguing they face a threat of FGM, but that does not appear to be the case. If the likelihood of FGM happening differs from family to family, then the attitude of the parents to the practice obviously influence the likelihood of it happening.