I've only fought one, Myxkion in Despise. I refused the pledge to the Shadowlords and their dagger. I did not suffer any special fire damage when he died. I think I was poisoned, with minimal damage, so no problem for me at the end.
If Andrew has his power from the Shadowlords, and if these Dragon People are planning to break their alliance with the Shadowlords, then Andrew could well be the "human" and his pledges the "week" people who joined him. But that doesn't mean that these Dragon People are on our side, they may be planning their own takeover. They call our lands their long ago home. What that means to us we don't yet know.