eskatonic:
Since the Symbiot Wars ended 50 years before the start of the Emperor Wars, it would have been a looong time ago, by Vorox reckoning, I think.
Well the Symbiot Wars hadn't actually
ended 50 years before the start of the Emperor Wars, merely "calmed" according to the 2nd ed rulebook. Since the Symbiot Wars began in 4900 and the Emperor Wars began in 4956, that would mean the Symbiot Wars "calmed" around 4906 - after just 6 years. But we know it wasn't until after 4955 (when the Eskatonic Order was officially accepted into the fold) that "the Church unleashed other Eskatonic Order priests and rogue psychics (promised absolution for their service) onto Stigmata" and "the Symbiot War was brought to an uneasy standstill."
That's a huge gap (50+ years) between the Symbiot Wars "calming" and the point when the "long, protracted guerrilla battle on the frontier was at an end, and an uneasy silence descended upon the front." So this incident with Vorox commandos being dropped on Stigmata and converted by the Symbiots could very well have taken place sometime during those 50+ years before the Manifest Light and Scions of Zahl beat back the Symbiots on Stigmata.
Actually, the only way the canon can be interpreted in such a way that it doesn't contradict itself is if this "calming" of the Symbiot Wars refers to this:
"Finally, in one area, surprisingly and for no apparent reason, the tide was turned and the Symbiot forces pushed back. Upon investigation, it was discovered that two people were largely responsible: Friar Berthold of the then-heretical Eskatonic Order and Damiana, a Charioteer trader."
So this could be what the canon is referring to with the Symbiot Wars "calming" 50 years before the Emperor Wars began. Otherwise, it contradicts itself by saying that "the Symbiot War was brought to an uneasy standstill" by theurgists and psychics after the official acceptance of the Eskatonic Order into the Church's fold, which happened in 4955. We would have to interpret the Symbiot Wars "calming" and their being "brought to an uneasy standstill" as two separate events, 50+ years apart, even though they sound like the same thing.
Of course, it's also conceivably possible that the authors originally intended the Eskatonic Order to have been brought into the Church's fold sometime between 4900-4906 (meaning the Symbiot Wars would only have lasted about 6 years before this "uneasy standstill"), with the Emperor Wars beginning "fifty years after the Symbiot Wars had calmed, leaving a tense and fearful populace waiting for the next alien expansion" - and then subsequently forgot about that and changed their minds, placing the official acceptance of the Eskatonic Order by the Church in 4955 instead.
But I'd prefer to go with the first interpretation, since I'd rather not start doubting the authors' accuracy with dates of landmark events in the timeline. Besides, 6 years can hardly be called a "long, protracted battle."
Regardless, in conclusion: even if the Symbiot Wars came to a standstill in the late 4950's and even if Vorox were dropped on Stigmata right up until that point (unlikely), those Vorox who were subsequently discharged from service in the Stigmata Garrison (even if assuming they were merely adolescents by Vorox standards at the time) would now be at least 50 years old or more in 4996, which is "ancient" by Vorox standards. If those Vorox were discharged from service anytime before about 4940 or so, they are probably all or almost all dead by now. So unfortunately, that particular concept probably isn't viable in this game's time period. But you could still play a Vorox ex-commando of some sort now serving as a Muster mercenary or as a noble's personal bodyguard or in some other capacity.