There are no hard rules here for there to be loopholes in. Basically, it provides some symbolic legitimacy to the wielder, but only if they are known to have proven worthy of wielding it - and that's entirely subjective.
Bo-Katan lost it, we don't know how, and Gideon got his hands on it. Whether he took it from her himself or not, he's a powerful and elusive Imperial Moff, a worthy adversary to win it back from. Since Din defeated Gideon he's now even more worthy.
But subbing in a patsy to take the fall? How do you see that flying with the Mandalorians? It's got to be a pretty hard sell.