The Nekro are still an intelligent society, if a very logic one. The Geth of Mass Effect are a good example for them (or even more so the Reapers *coughcough*). Sticking to Geth, (spoiler alert) we already see a divided society, because of different interpretations, assumptions, ideas, prognostics, beliefs, calculations.
In a way, the same could be applied already to the L1Z1X "Mindnet" after all.
Personally, I see the Nekro Virus in the Galactic Council, seen by the other races, as "a major player", "an obvious threat", "still sending Representatives to speak for them and communicate". So they can't be that evil and against everything, right?. But dangerous they are, that's an obvious fact for everyone.
Why don't they vote though?
Are they seen as too "young" and/or "dangerous" yet to consider them the right to cast votes? Listen to their opinions on subjects, yes. Throwing their influence into the fray already, no.
Is it their personal agenda to stay neutral on everything and just pull strings behind the scenes?
Both probable cases.
Their representatives indicate the first possibility though. They have to resort to much more menacing and psychological warfare in the council.
Players always have to chose if they vote the way the want and in return benefit the Nekro. Or risk losing a potential agenda to not benefit the Nekro - which in turn might be positive for the Nekro as well, or at least not negative. The Nekro try to create win/win situations. Calculating at it's best.
They always take advantage of other players fears. Constant harassment, constant growth by these, a threatening mothership, wherever it goes, and their representatives are falling right into that schematic.
Their one Councilor fits well into all of this. The Nekro will only use it in safe and important situations, having the other players lured into a standard pattern for example. Or where it can wreak the most havoc (but if that's sensible is another question).
In the case of it's use, the tale could have been something like this:
For the first time, the Nekro Virus's representatives ask for permission to speak. Many political analysts agree that it was the Flaming Speech the previous Councilor held, that has ignited this spark of urgency seldom seen in a political member of the Nekro Emissaries. The arguments against the current agenda where all precise and logical, and many yet indecisive representatives, delegates and important members of the great and minor races where nodding in thought as they listened.
But there the records suddenly turned into the white snow and noise of lost signals and a rumble was heard and felt all through the center hills of Mecatol City. Sapphire security glass and dust rained down the perimeter around the Galactic Council. Only a few citizens where wounded. The tall building housing the council was mostly intact as well, almost no rubble fell. But the council itself? All dead, except for a few of the sturdiest, yet traumatized and without memory. It took a whole week for Dirzuga Ohao to regrow enough to be able to communicate on verbal terms again. He too could not remember what actually happened.
Gantan Twain, chief-investigator, found the case puzzling. All relevant technology misfunctioned mere moments before the explosion, according to the few extracted logs of personal devices present in the councilors' hall. Yet the building's recording devices in the relevant stories fell out minutes before, during the Nekro's speech. So noone really knows what happened. All that is known is that the Councils Electory System shows that a majority of the Council voted for the last agenda - against the Nekro's proposal. So it must be someone else responsible for this burning wound in galactic democracy and struggle for diplomatic peace.
Noone found the remnants of the tiny Proxy-Scout that infiltrated the mainframe, undetected, thanks to reverse-engineered Naalu physical cloaking technologies. On stand-by for two and a half years it waited between condensators, cables and pipes, listening. Them, when it received command, it struck! Disabled, deleted, manipulated records, tweaked the casted votes the way it should, shrouded it's tracks and then left. Seeking an abandoned ventilation shaft to heat itself up to melt and vaporize itself.
The authorities would need too much time to find any sensible leads, if at all, to be connected to the Nekro. In the end rendering a likely, current faction of anti-galactic guerillas as terrorists and responsible for the event. After all, the populace can't be left with the image of incapable police, secret service and military.
Months later Twain resigned for personal reasons. Deep down he could not bear the giant political lie that hit not just the opposionists, but their settler's world. Twain new it was an excuse to not let the governing parties look the fool. He knew the culprit wasn't found. It all stunk like a huge cover up. It all stunk too much that, in the end, it had to be the Nekro after all. The perfect alibi. The most hated be victim when they were finally, for the first time, with the council. But what would they have gained the most benefit from? The current coalition of Races did not want to hear his theories. They did not want to ignite new strife from the Nekro, as their worlds were - currently - safe from them.
Gantan Twain sighed as he leaned back in his chair, a solemn wind at the curtains. He smelled at his whiskey. It had lost it's fragrance. It tasted metallic.