How should Augury work when the course of action relies on a skill check?

My party’s Cleric has just picked up Augury. It’s clearly a spell that garners some understandable confusion, but I don’t think this precise question’s been asked before.

How should I, as DM, answer Augury when the good or bad outcomes of a proposed course of action hinge on a skill check, which is random?

To provide a concrete example, suppose the party need to recover some battle plans from within an enemy encampment. In the dead of night, the Cleric casts Augury, proposing: “The rogue sneaks past the sentries and takes it from the command tent”. It’s a fine plan, one I expected them to try, and it will work perfectly if the Rogue rolls at least an 11 on their stealth check – a 50% chance. But if they roll under, the alarm will be raised, and the Rogue will likely be captured.

This isn’t “Nothing”, and it isn’t “Weal-and-Woe” – the result is definitely one of Good or Bad, and it isn’t both. It also isn’t contingent on any subsequent effects that would change the outcome. So how should I answer?