Her protectiveness of Kira being part of a con like that... sounds convoluted and I think the writers are better than that. Far easier to believe Mrs. S really does have some good intentions

Sarah obviously didn't tell anyone exactly how long she would be gone for (probably because she herself didn't know), but from the way Felix was mad at her for it it seemed they assumed it would only be a matter of a few days. Definitely not almost a year. After weeks and months of waiting, I believe a Mrs. S who was in cahoots with the Neolutionists would have realised she had a golden opportunity and more than enough time to cook up a convincing story to fool Sarah upon her return. Just a thought