HappyDaze said:
It's unlikely - primarily because such groups tend to be led by one of their own who has risen to power through cunning, ruthlessness and (commonly) murder. An outsider, of any kind, is ill-positioned to become Dracon of a band of Trueborn by merit of being an outsider.
My stock answer in cases like this is "it'd be so rare as to be essentially unhead of" - I'm not likely to include such a thing, and while you're welcome to take a different approach, I'd regard it as the exception, not the rule.