According to the info I read online, the Hradus system, while just inside the The Third Imperium, has the highest population of Aslan found anywhere in the Imperium territories. 80% Aslan, and only 20% human. So I figured the Aslan there will be somewhat 'softened' version of more traditional Aslan found outside the The Third Imperium. Trasko will be even one step more removed in that he discovered early in his life he's not cut out to be a warrior, but found a measure of respect being able to properly outfit Aslan warriors with the armor & weapons they need. One of his favorite aspects of his business is sourcing ancient (by Aslan standards) Aslan ceremonial armor & weapons, and selling them to more traditional Aslan who thrive on the 'old ways' of their tribes.The Aslan Merchant can easily have grown up in the Third Imperium or on a planet in the Voidsedge and been a little more culturally diverse. I think that works fine.