The official vokun assessment of Yantra was that it had little to offer the Empire. It's natives were primitive (at best they had mastered iron) and demonstrated a pervasive culture of nonviolence so ingrained that they were insuitable for military conscription. The ibglibdishpan analysts verified that there had once by an advanced civilization on Yantra: the environment had been finely tuned, nanotechnology (though dormant) still permeated the biosphere, and seemingly primitive stone structures (shrines, mostly, for the superstitious Yantrans) actually showed complex femto-level engineering.
Obviously, the primitives had no knowledge of these technologies, and there was no indication they ever did. The vokun are an incurious species. They assumed some great pre-Collapse civilization had left its mark and moved on. Yantra was only usefully as a pleasure world; it's mostly tropical clime and pliant, simpleminded, and exotically attractive populace provided an ideal place of relaxation for vokun nobility.
The ibglibdishpan were vexed by the anomalies. It only took a few in the continuing series of seemingly random network and equipment failures that have plagued the Imperial conquest of Yantra for them to deduce the truth. They were not at all surprised when vokun junior officers began to disappear or have unusal accidents--never frequently enough to arouse suspicion on the part of the vokun, but a detectable statistical signal, nonetheless. For reasons known only to them, the ibglibdishpan have kept their conclusions to themselves.
