I always keep multiple saves. Even without running into problems like this, they are handy to try quests in different ways, or go back for something you missed. Several times I took speech options just to see the results, and reloaded to go through again and pick 'good' options (sometimes you can be a bastard just for the fun of it, sometimes you can extort or threaten a better reward out of people, but you usually get as good a result by being nice).
