ITV does the 'missing/unrecognised body' trope to later undo deaths, right?
But Naira's soul will be around now, so her death is permanent. There was no point making her body unrecognisable apart from CVs being sadists. They could have easily given Naira a proper, realistic death like Gayatri.
Also, this track is a huge gamble. If it fails, there's no way to undo it while retaining Kaira.