Unfortunately Sheilagh can't bring herself to realise that there can only be one timeline, something which seems almost impossible to maintain, and you are playing God whether you seek to restore the timeline or not. If you do nothing you are condemning trillions who will not exist, and if you do something to restore the timeline you have the same effect but the desired outcome. Morality it seems is out of the question for rationalising the work which the Temporal Integrity Commission does.