Thank you for the question. I think it's quite useful in terms of illustrating this difference.
You're quite right that, in the context of a revocation of a licence, if that were to be, let's say, contested and eventually determined in a courtroom, the standard that would apply would be on a balance of probabilities, which for the layperson is like “50% plus one” certainty, so more likely than not. I think that's a good way of understanding what a balance of probabilities means.
Reasonable suspicion is a standard that's used throughout the code. It's definitely lower. In fact, it's the lowest known to criminal law. It really just means.... Well, first of all, we're talking about evidentiary standards, so with respect to the amount of evidence, obviously it's not just a question of quantity. The nature and quality of that evidence will matter. Effectively, it's a credible possibility that the thing suspected occurred or will occur, depending on how it's directed.
I should note here that it's modified by the subsequent language “may have engaged”, so that's the thing to be proved, a mere possibility that a thing may have happened.