Were I in conversation with Myrielh, I would point out that basically every comparison she made between goblins and humans was incomplete, demonstrating a commonality of outcome without demonstrating a similar lack of alternatives.
I would, likewise, point out that however efficient slavery is today at producing overall prosperity (without accepting her claim) - necessity is the mother of invention, and those who stand atop the pillars of present day prosperity are often hostile to alternatives that would weaken their position. In-character, maybe slavery is necessary for the druchi prosperity, or maybe it isn't, but it is far less likely that they find a better alternative if their acceptance of slavery is rendered painless to them. As little 'ol mayfly humans, the empire is well disposed towards finding such an alternative far quicker, and any increase in reliance on the druchi opens them to political influence from those in druchi society who would stand to lose if slavery as an institution were replaced.
However affable Myrielh presents herself, she is not all Druchii, after all.
This is all more or less sufficient condition to me to reject any action which enables the encroachment of Druchii influence on the empire, and any dealing with Ylrishen or Myrielh in particular. There is little we even stand to gain from taking those risks when we have the alternative of doubling down on stronger ties to ulthuan with the elfcation, and have the waystone project as an alternative to the Druchii as a stick to get ulthuan to put more chips on the table.
A personal transaction though, where we could isolate the institutions of the empire and Eonir from the institutions and power brokers of the Druchii? That might be more feasible. Perhaps with Captain Maktig, if we gain the opportunity to vet them further. Even if the society and its institutions are corrupting, if we find a suitable individual to work with, it's not unthinkable - we just have to sharply limit the scope to those we can trust, and keep it under the table so others don't take our example as proof of opportunity they can get in on with less scruples.
And yes, "suitable" can include "was uninvolved with the slave trade". Again, the bottom line is that it's dangerous and risky, especially in the long term, to open relations with the dark elves as a polity - but that individuals within might be feasible, if we can find the right one(s).
