I think no measure whatever would hinder people from savescumming. So I would say, leave it as it is, to spare ressources. But make the dice animation skippable, it's annoyingly slow. If there is a way to skip, I just did not discover it yet.
Otherwise it is a training effect. The game should tell you that also with a "fail" you get an interesting and successful story. Of course most of the players would not read/listen. In my case, I cannot remember that I reloaded even once when I did not "succeed" in dialogs. I reloaded on several occasions when I "succeeded", because I wanted to fail (to get a fight). There are only very very few checks in the EA in which I wanted to succeed 100% of time. I cannot remember a dialog, just checks for chests or "doors". And usually the reroll possibility from Inspiration is enough. The only situation where I would reload till success is the lever which allows you to skip the tedious moon puzzle (I don't like puzzles).
To the example in the OP's post, it's not a big problem if you fail the check at the door of the ruins. You get trapped but the following fight against the alerted bandits is not more difficult than if you succeeded in the dialog, I find it even easier to a certain extent. The more the player has such experiences, the more he/she may be inclined to accept dice rolls.
