The Winter of Discontent, Raumeni-style
The Raumeni of the Three-Tone Alliance (three major and several dozen minor clans fighting under the same banner) had always seemed a 'decent enough sort' to the Codexians. Borderlanders, through and through, they included some of the most enterprising 'bugs' around. One of their member clans had even participated in the long and ill-advised war of first contact against the humans. Yet, they were still the ones who did most of the trade with the humans, and were most certainly the ones who dealt with them on an everyday basis. These clans, young and vital as they were, rankled under the strictures of the Confederacy. As an institution, it existed solely to prevent a radical schism amongst clans with inherently distinct interests. However, it could do so only with the assent of its constituent members, and was barely suited to actually resolving internecine grievances. When one of these escalated in the 260s to the point of open conflict, there was little the Confederate 'government' could do.
After all, the Raumeni clans each maintained their own militaries. None depended on the Confederacy for protection - quite the opposite was true, in fact. Therefore, as soon as the Three-Tone Alliance began fighting the Four Suns of the Red Nebula, and its other enemies across the Raumeni Confederacy, the situation immediately became untenable. The Confederate government collapsed in a ruined heap within eight months, and bloody battles began to exert a terrible attrition on the Raumeni belligerents. Hundreds of vessels were destroyed in mere months, and a great many of the insectoids perished. Simply sitting back and observing the course of the conflict was certainly an option, but for the Codexian government the only possible course of action became clear, as soon as trade volume dropped by some thirty percent. To allow this state of affairs to go on would ruin innumerable Codexian businesses, not to mention the unpredictable consequences for long term relations that the conflict might have entailed.
It was quickly decided that Codexia would have to act. In 263AU, roughly a year and a bit into the Raumeni Civil War, the bulk of the Second and Sixth Fleets transitioned into Three-Tone space, as part of a 'peacekeeping' initiative. Led by Admirals JP Gromyn and Michael Augustus, the Codexian Naval forces involved were to act 'in a humanitarian fashion, protecting Raumeni civilians from wartime depredations and thereby helping to resolve the conflict.' This, essentially, was a diplomatic veneer 'covering up' the outright military support the Codexian government had allotted to the Three-Toners. Codexia itself did not mobilize, nor adopt measures that would put it on a wartime footing. Rather, the Civil War was treated as a limited conflict requiring only a moderate military commitment to ensure a favourable outcome.
Unfortunately, this evaluation of the situation at hand proved to be highly optimistic. The presence of the Codexians certainly won otherwise unwinnable battles for the Three-Tone Alliance, but the strategic balance remained precarious. And losses began mounting rather quickly. The Raumeni were deceptively powerful. Though no single clan or collection thereof could match Codexia's potential during a full blown war, the Raumeni, as a whole, were clearly a different story. The smallest of the clans could still call upon some military might - while the greatest had entire Codexian fleet-equivalents in their orders of battle. The armadas of the Four Suns were, in their own right, quite vast. And they made the humans bleed. By 264AU, units of the Seventh and Ninth Fleets were dispatched to the contested frontage. Then, the Seventh was fully committed. Yet, it was clearly not enough. The Battle of the Brothers Epsilon was as decisive a victory as any of the war, for the Three-Toners, but the Four Suns refused to give in. Though possessing superior strategic mobility and working stealth cloaks, the Codexians could not tilt the war decisively in favour of their client faction.
It was in 265AU, the third year of the war, that the Codexian government began suspecting that there was another party to the conflict, backing the forces of the Four Suns with military intelligence, funds and other forms of clandestine support. The hints had been there all along, but no one was looking for them. Within months, Codexian intelligence operatives had uncovered a name. The Hin'in. Aside from that, there was not much information on the unseen foe. It was clear that their horse in the race some called the Civil War was the deadly foe of the Three-Toners. None of the other factions involved seemed to attract their patronage. Said patronage of the Four Suns was having a deleterious effect on Codexian efforts at resolving the conflict, once and for all. Something had to be done. And quickly! The public would not long stand for an undeclared war that was costing thousands of human lives, and that would result in a flood of insectoid refugees into Codexian territory.
Do you... bolster your forces in the Raumeni territories and launch a savage, direct offensive against the Four Suns, in the hopes of flushing out the Hin'in?
OR
Do you... work the back channels, in an attempt at establishing a line of communications with these new aliens? Perhaps they could be reasoned with.
OR
Do you... ignore the Hin'in involvement in the conflict and concentrate on solidifying the gains of the Three-Toners, by calling the Four Suns to the negotiating table? After all, they are also businessmen, and this was not proving so good for anyone's business.
***
The Barbarian apologizes, lads, he was not trying to give the impression that this war was going to entail the full mobilization of Codexian resources. That sort of thing requires - much as in the real world - the impression of an existential threat, at least.
we have both FTL and wormhole drives
EDIT: Just for the sake of clarity: you have knowledge of both, but only use wyrmhole drives. In this sense, it's an either/or proposition. The drives in question are too big, too power-consuming and too expensive to be used jointly on any practical vessel. The Raumeni still possess a very clear superiority in tactical mobility, as such.