Tsaritsa created the Fatui 3 years after she becomes Cryo Archon.

Dottore and Sandrone probably not born at this point so they couldnt have Delusions, enhanced soldiers and other robots.

The only members exist at that point are Pierro, Captino, Columbina, Signora and probably Pulcinella.

Pierro is the director so he already there with Tsaritsa.

Since Columbina was recruited after Sandrone already a Harbinger, she couldnt be one of the first Harbinger.

Capitano, Signora and Pulcinella are unknown when they joined the Fatui.

So either Pierro solo the fae princes and their army or he, Capitano and Signora fought together.

Considering the Fatui still new here, how they managed to conquer the lands of the fae princes in a year ?